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Journal articles on the topic 'Chemical fire engines'
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1
Kravchenko, N. G., I. A. Kozlov, V. K. Shchekin, and E. A. Efimova. "CLEANING CHEMICAL COMPOSITIONS FOR AIRCRAFT ENGINES (review)." Proceedings of VIAM, no. 1 (2021): 105–13. http://dx.doi.org/10.18577/2307-6046-2021-0-1-105-113.
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Different detergent compositions for removing contaminants from metal surfaces are considered. Components of detergent compositions and their effect on the properties are described. Examples of promising studies in this area are given, including those related to improving detergent properties, anticorrosion characteristics, fire safety and environmental friendliness. Attention is paid to compositions that provide simultaneous washing and preservation of metal. It is reported to determine effect of detergent compositions on other materials of aircraft.
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Han, Yong-taek. "Study on the Development of Multi-Purpose Fire Engines through Vehicle Safety Factor Design." International Journal of Fire Science and Engineering 36, no. 3 (September 30, 2022): 18–28. http://dx.doi.org/10.7731/kifse.22d06965.
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With the recent rapid economic growth, the construction of high-rise buildings such as new town apartment complexes, residential-commercial complexes, and office buildings has increased. This study thus attempted to develop a multi-purpose fire engine to enhance the response to a fire and rescue efforts in line with the steady increase in the demand for safety in high-rise buildings, through a design that combined techniques that focused on large ladders and a midsized 5-ton fire pump engine. A ladder function was added to the most widely used fire engine, with the design incorporating a maximum ladder height of 20 m for fire suppression and lifesaving. A basket was fitted to the end of the ladder to enable firefighters to safely perform these tasks, while the outrigger was designed to vertically descend to allow ladder work as long as vehicle entry is possible despite illegally parked cars. Based on the chassis of a commercial 5-ton fire engine as a type of conventional midsized pump engine, the result was a multi-purpose fire engine developed for special uses that require both fire pump and ladder functions. The multi-purpose fire engine was designed in consideration of safety factors for the direct rescue of people from buildings using a basket rated for a maximum load of 250 kg, through the application of a boom in addition to the common fire pump. It is expected that after their rapid arrival at the scene of a fire, such multi-purpose fire engines could be used for firefighting or lifesaving at relatively low 2-6-story buildings. It is anticipated that the present investigation and other relevant studies will allow the application of this novel design to various other vehicle types such as water tanks, chemical tanks, and rescue vehicles.
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Li, Tianxin, and Yan Jiao. "Simulation study on the effects of different flow conditions on the combustion of square fire." E3S Web of Conferences 136 (2019): 02039. http://dx.doi.org/10.1051/e3sconf/201913602039.
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Combustion is a process in which light and heat are produced when a series of complex chemical reactions take place. Our life has long been inseparable from combustion, such as coal for power generation, fuel oil for car engines, rocket propulsion, waste incineration; but at the same time, with the development of the city, the damage caused by frequent fires is more serious. The purpose of this topic is to study the laws of plane flame combustion under different conditions. It is proposed to simulate the real plane fire combustion conditions with different flow conditions such as wind speed, combustion space and opening conditions, and propose relevant cognition and Countermeasures Based on this. Through the analysis of the above points, we can simulate the combustion situation of different weather and floors un-der different real conditions, different scale indoor environment and boundary conditions, so as to carry out new building requirements and planning, and lay a referential foundation for the evaluation and control of the fire scale.
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Y, Alex, and Roji George Roy. "Production, Quantitative Analysis of Fatty Acids, Engine Performance and Emission Characteristics of Biodiesel Fuel Derived from Virgin Coconut Oil." International Journal of Innovative Science and Research Technology 5, no. 7 (August 18, 2020): 1397–404. http://dx.doi.org/10.38124/ijisrt20jul853.
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Biodiesel has become more attractive recently, because of its environmental benefits and the fact that it is made from renewable resources. Over the past few decades, most of the countries depending on diesel engines for transportation. Some of its valuable advantages like highest thermal efficiency made it very popular. At the same time, the cost of diesel fuel is increasing, due to the depletion of fossil fuels. In this current scenario, we need an alternative fuel instead of diesel fuel. Many of the researchers have successfully placed several works on generating energy from different types of alternative sources including solar and some kind of conversion processes including renewable agricultural products into liquid fuel. One of the biggest challenges for developing countries in relation to energy consumption is to develop and implement technologies that help to improve efficiency of automobile engines, also to reduce the emissions of harmful gases and particulate matters. In order to avoid environmental impacts, emissions are reduced or eliminated by introducing renewable energy resources. The present research chronicles the production and testing of renewable biodiesel fuel derived from virgin coconut oil on a diesel engine, to analyses the engine performance and emission characteristics. In the first phase of work, production of biodiesel fuel from virgin coconut oil using transeterification process with two types of catalysts (homogenous and heterogeneous). The preliminary results shows that, with the addition of homogenous catalyst called Potassium Hydroxide (KOH) with methanol shows much higher activity than that of heterogeneous catalysts, and it shows more similar properties with diesel fuel. The results obtained from the chemical test and physicochemical properties of transesterified biodiesel fuel clearly proves the above-mentioned statement. The chemical tests such as GCMS and FT-IR clearly shows that the biodiesel fuel has sufficient amount of volatile components and functional groups. Then, physicochemical properties include, Fire point, Flashpoint, density, and viscosity were analyzed. Finally, Engine performance and Emission characteristics were analysed to confirm, whether this biodiesel fuel is suitable for diesel engines, without any engine modifications. It was found to be, the transesterified virgin coconut oil biodiesel has similar properties to that of the diesel fuel. From the physiochemical properties and engine performance clearly shows that, coconut oil biodiesel is suitable for diesel engine on blending, at a blending percentage level of 20% with conventional diesel fuel. Since the obtained transesterified biofuel can be used as an alternative fuel for diesel engines. The several journal reports and find outs from experimental investigation clearly depicts that the efficiency of the transesterified biofuel mainly depends upon the amount of catalyst adding and type of catalysts present in the biofuel, whether it is homogenous or heterogeneous catalyst is suitable with methanol. Finally, from the analysis made from biodiesel fuel. Coconut Oil Biodiesel fuel has less emission characteristics than that of the diesel fuels.
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Atkinson, Simon. "Fire seal is designed for use on aircraft with engines that operate at high temperatures." Sealing Technology 2020, no. 11 (November 2020): 5. http://dx.doi.org/10.1016/s1350-4789(20)30352-4.
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Chen, Shaoji, Jie Tian, Jiangtao Li, Wangzhen Li, and Zhiqing Zhang. "Investigation of the Performance and Emission Characteristics of a Diesel Engine with Different Diesel–Methanol Dual-Fuel Ratios." Processes 9, no. 11 (October 29, 2021): 1944. http://dx.doi.org/10.3390/pr9111944.
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In this paper, the effects of different diesel–methanol blends on the combustion and emission characteristics of diesel engines are investigated in terms of cylinder pressure, heat release rate, cylinder temperature, brake specific fuel consumption, thermal brake efficiency, brake power, and soot, nitrogen oxides, and carbon monoxide emissions in a four-stroke diesel engine. The corresponding three-dimensional Computational Fluid Dynamics (CFD) model was established using the Anstalt für Verbrennungskraftmaschinen List (AVL)-Fire coupled Chemkin program, and the chemical kinetic mechanism, including 135 reactions and 77 species, was established. The simulation model was verified by the experiment at 50% and 100% loads, and the combustion processes of pure diesel (D100) and diesel–methanol (D90M10, D80M20, and D70M30) were investigated, respectively. The results showed that the increase in methanol content in the blended fuel significantly improved the emission and power characteristics of the diesel engine. More specifically, at full load, the cylinder pressures increased by 0.78%, 1.21%, and 1.41% when the proportions of methanol in the blended fuel were 10%, 20%, and 30%, respectively. In addition, the power decreased by 2.76%, 5.04%, and 8.08%, respectively. When the proportion of methanol in the blended fuel was 10%, 20%, and 30%, the soot emissions were decreased by 16.45%, 29.35%, and 43.05%, respectively. Therefore, methanol content in blended fuel improves the combustion and emission characteristics of the engine.
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Kuzminskaya, A. M., M. V. Buzaeva, and O. V. Ageeva. "Modern methods to reduce evaporation and ensure safety when storing petroleum products in tanks." Technology of technosphere safety 94 (2021): 65–75. http://dx.doi.org/10.25257/tts.2021.4.94.65-75.
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Introduction. With long-term storage of gasoline in large-capacity tanks, the problem associated with their volatility becomes urgent. Evaporation of petroleum products and gasoline leads to a change in their physical and chemical properties, a decrease in the yield of light petroleum products during oil refining, and a deterioration in the performance characteristics of engines. In this regard, it becomes difficult to start engines, their reliability, fuel consumption increases and the service life is reduced. Lost light hydrocarbons pollute the environment and increase the fire hazard of enterprises. The aim of the work is to identify effective, inexpensive and safe methods for reducing the volatility of oil products, including gasoline, when stored in tanks. Research methods. A retrospective analysis of studies on the problems of reducing losses of petroleum products during their storage, transportation and use is carried out. Technical and organizational methods for reducing the evaporation of fuels and the use of chemical additives as an inexpensive and effective method for solving the problem of the volatility of gasolines are considered. The conclusion about the efficiency of using chemical additives to fuels to reduce volatility has been substantiated. Results and their discussion. Conclusions are made about the possibility of using surfactants as additives to reduce the evaporation of gasolines during long-term storage in tanks. The analysis of the main components and methods for the synthesis of surfactant compositions capable of creating a surfactant film at the liquid-atmosphere interface, which protects the liquid from evaporation. Conclusion. Reducing the volatility of gasoline with the use of inexpensive and effective additives introduced into the fuel in small quantities, not only reduces the explosion and fire hazard during storage in large tanks, reduces losses, but also prevents the negative impact on the environment from the ingress of low molecular hydrocarbons into it. Key words: volatility of petroleum products, losses during storage of gasoline, methods of reducing volatility, additives.
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Fuke, N., M. Sato, H. Shiga, M. Yamashita, T. Yokoi, Y. Kobayashi, A. Kobayashi, and R. Ikita. "(P2-58) A Multicasualty Event of Multiple Burn Victims Caused by Spout of Heated Hydrochloric Acid in a Chemical Plant." Prehospital and Disaster Medicine 26, S1 (May 2011): s154—s155. http://dx.doi.org/10.1017/s1049023x11005024.
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BackgroundA sudden break-down of a heat-exchanger in vinyl chloride plant resulted in that 141 °C, 23% concentration of hydrochloric acid spouted out over the workers around it. Eight workers suffered and Ichihara City Fire Department was deployed in response to the call 3 minutes after the onset of the incident, 17 vehicles including 5 fire engines, 6 ambulances, and two helicopters. Finally three severely (> 80% of TBSA) burned, two moderately (20–80%) burned, and three slightly (< 20%) burned victims were identified and triaged. One severely burned was transferred at first to the closest tertiary care hospital (TUCMC) which existed within 2.5 km distance by an ambulance and other two and one moderately burned were transferred by helicopters to the neighboring tertiary care hospitals. Another moderately burned one was sent to TUCMC by an ambulance about 30 minutes later than the first one. Three slightly burned victims were sent to a local hospital and treated as an outpatient. This casualty mission was ended by 120 minutes after the call. Two among the three severely burned patients lost their lives but another severe one and two moderately burned were survived. Conclusions: With these considerations, the management of this multiple burn casualty was successful, partly because of small number of the victims and of that the incident occurred in a weekday morning.
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Wu, Gang, Jiaoxiu Li, Hao Guo, Xin Wang, and Guohe Jiang. "Numerical Method for Predicting Emissions from Biodiesel Blend Fuels in Diesel Engines of Inland Waterway Vessels." Journal of Marine Science and Engineering 11, no. 1 (January 3, 2023): 86. http://dx.doi.org/10.3390/jmse11010086.
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The use of alternative fuels in ships faces the dual challenge of emission regulations and cost of use. In this paper, the impact of biodiesel blends from cooking waste as a carbon-neutral fuel for inland waterway vessels was investigated. The software AVL FIRE was used to simulate the detailed chemical combustion process of a marine diesel engine running on D100 (pure diesel), B5 (5% biodiesel by volume), B10 (10% biodiesel by volume), and B15 (15% biodiesel by volume). The results showed that B5, B10, and B15 all provided a better air-fuel mixture and significantly reduced soot production. Based on the performance and emission values, B5, B10, and B15 cause relatively small differences in engine performance compared to diesel and are readily applicable in practice. Optimizing exhaust gas recirculation (EGR) and varying injection timing can further optimize biodiesel fuel combustion while reducing NOx and soot emissions. The results of this study are helpful for the application of waste cooking oil biodiesel fuel and reducing exhaust gas emissions from ships.
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Guo, Kangkang, Yongjie Ren, Yiheng Tong, Wei Lin, and Wansheng Nie. "Analysis of self-excited transverse combustion instability in a rectangular model rocket combustor." Physics of Fluids 34, no. 4 (April 2022): 047104. http://dx.doi.org/10.1063/5.0086226.
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A methane/oxygen mixture is considered to be an appropriate propellant for many future rocket engines due to its practicality and low cost. To better understand the combustion instability in methane/oxygen-fed rocket engines, the spontaneous transverse combustion instability in a rectangular multi-element combustor (RMC) was analyzed both experimentally and numerically. Severe combustion instabilities occurred in the RMC during repeatable hot-fire tests. The physical mechanisms were systematically investigated through numerical simulations based on the stress-blended eddy simulation and flamelet-generated manifolds method with detailed chemical mechanisms (GRI Mech 3.0). The numerical results for the frequency spectrum and spatial modes agree well with the theoretical analysis and experimental data. The driven regions of the combustion instability were identified on both sides of the combustion chamber through a Rayleigh index analysis. The longitudinal pressure oscillations in the oxidizer post were found to be coupled with the transverse pressure waves in the combustion chamber and led to periodic oscillations of the mass flow rate of propellant. Moreover, the mixing was highly enhanced when the pressure wave interacted with walls of the combustion chamber. Therefore, a sudden release of heat occurred. The pressure oscillations were enhanced by pulsated heat release. A closed-loop system with positive feedback associated with periodic oscillations mass flow rate of the propellant, and sudden heat release, was believed to account for the present combustion instability.
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Shakhov, S., and D. Saveliev. "ANALYSIS OF ACTIONS OF THE STATE EMERGENCIES SERVICE OF UKRAINE WHILE EXTINGUISHING FIRES ON ELECTRIC VEHICLES." Municipal economy of cities 1, no. 168 (March 25, 2022): 75–80. http://dx.doi.org/10.33042/2522-1809-2022-1-168-75-80.
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Electric and hybrid vehicles, which involve road accidents and fires, present unique risks associated with high voltage systems. These hazards are divided into three separate categories: chemical, electrical and thermal. The possible effects may vary, but are not limited to the size, configuration, and chemical composition of the battery. Operational and rescue units of Ukraine in case of road accidents are guided by the order of the Ministry of Internal Affairs of Ukraine and methodological recommendations. These documents cover actions during fires and emergencies in electric vehicles are quite concise and need to be significantly expanded and provide the necessary recommendations to prevent injuries to personnel during rescue operations and firefighting in this type of vehicle. The article comparative analysis of normative documents, methods and actions of rescue units of Ukraine with recommendations and methods of other states, in case of fires on hybrid and electric vehicles, identification of shortcomings in order to further provide recommendations for improving existing management documents, taking into account experience and practice abroad. According to the results of the analysis, the guidelines of the Rescue Service of Ukraine do not contain a clear list of exercises that can coordinate the actions of rescuers and increase their personal safety with the following sequence of actions: car identification, immobilization, disconnection of power sources, rescue. Actions on extinguishing cars are very briefly reviewed, it is not clear for what reasons the use of air-mechanical foam is prohibited. Methods of extinguishing ordinary cars with internal combustion engines on gasoline and diesel, and recommendations for the use of fire extinguishers during firefighting on these vehicles in the regulations are not available at all. electric and hybrid vehicles need significant revision and improvement, taking into account the experience of other countries in the field of rescue and firefighting.
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Shakhov, S., and D. Saveliev. "ANALYSIS OF ACTIONS OF THE STATE EMERGENCIES SERVICE OF UKRAINE WHILE EXTINGUISHING FIRES ON ELECTRIC VEHICLES." Municipal economy of cities 1, no. 168 (March 25, 2022): 75–80. http://dx.doi.org/10.33042/https://doi.org/10.33042/2522-1809-2022-1-168-75-80.
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Electric and hybrid vehicles, which involve road accidents and fires, present unique risks associated with high voltage systems. These hazards are divided into three separate categories: chemical, electrical and thermal. The possible effects may vary, but are not limited to the size, configuration, and chemical composition of the battery. Operational and rescue units of Ukraine in case of road accidents are guided by the order of the Ministry of Internal Affairs of Ukraine and methodological recommendations. These documents cover actions during fires and emergencies in electric vehicles are quite concise and need to be significantly expanded and provide the necessary recommendations to prevent injuries to personnel during rescue operations and firefighting in this type of vehicle. The article comparative analysis of normative documents, methods and actions of rescue units of Ukraine with recommendations and methods of other states, in case of fires on hybrid and electric vehicles, identification of shortcomings in order to further provide recommendations for improving existing management documents, taking into account experience and practice abroad. According to the results of the analysis, the guidelines of the Rescue Service of Ukraine do not contain a clear list of exercises that can coordinate the actions of rescuers and increase their personal safety with the following sequence of actions: car identification, immobilization, disconnection of power sources, rescue. Actions on extinguishing cars are very briefly reviewed, it is not clear for what reasons the use of air-mechanical foam is prohibited. Methods of extinguishing ordinary cars with internal combustion engines on gasoline and diesel, and recommendations for the use of fire extinguishers during firefighting on these vehicles in the regulations are not available at all. electric and hybrid vehicles need significant revision and improvement, taking into account the experience of other countries in the field of rescue and firefighting.
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Sesták, Jaroslav. "The role of order and disorder in thermal and material sciences part 2: Scientific world and new insights." Journal of Mining and Metallurgy, Section B: Metallurgy 39, no. 3-4 (2003): 407–25. http://dx.doi.org/10.2298/jmmb0304407s.
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The notion of heat is thoroughly analyzed and its historical links are search particularly with relation to both the Greek philosophy (Mile in print sians Pythagoreans, atomists, etc) and the in the present day thermal physics. Fluctuation, spontaneity and chaos is discussed. Thermodynamics is reviewed in the relation to both the traditional development and the modern description of disequilibria (open systems). Effect of dissipation is shown often to provide new, self-organized structures. Exploitation of fire and its conscious use as a manufacturing power are analyzed in terms of generalized engines to act in the sense of as the information transducers. The part 2 reveals the impact of mathematics as explained on some simple cases showing development of basic ideas (vibration, topology, bifurcations etc). Earth thermal environment is discussed in relation to the existence of life (antropy principles). Alternative theory of reaction-diffusion model of the space-time is put in contrast with big bang hypothesis and related to the herewith-discussed specialty of self-catalyzed chemical reactions. The text gives a consistent view to various historical and modern concepts that emerged during the gradual understanding of order and disorder.
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Jahja, Felicia Erika, and Muhammad Ilyas. "Literature Review: Cancers Among Workers Exposed To Perfluorooctane Sulfonate (PFOS)." Indonesian Journal of Community and Occupational Medicine 1, no. 3 (March 25, 2022): 179–88. http://dx.doi.org/10.53773/ijcom.v1i3.28.179-88.
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Introduction: Cancer is a disease with a high mortality rate in Indonesia. One of the chemical exposures that can cause cancer is perfluorooctanesulfonyl fluoride/perfluoro octane sulphonate (PFOS). PFOS is a chemical that is widely used due to its diverse functions, including use in fire extinguishers, waterproof materials in food boxes and furniture, and household hygiene products. Long-term exposure to workers affected by PFOS is suspected to be one of the risk factors for cancer. Methods: The author conducted a literature search of online search engines in 3 sources PubMed, Google Scholar, and JSTOR databases. The inclusion criteria in this study are articles in English, full text available, and conducted on the working population. The author has not restricted search within the last 5 years due to the limited reference of the topic. Results: Out of a total of 5 articles examined, the authors found the incidence of bladder cancer in workers as much as 1.28 times, there was even a death rate of 12.77 times in workers with PFOS exposure due to bladder cancer, although the results did not statistically significantly. Other studies have shown increased levels of PFOS in the blood but were not associated with changes in other laboratory examinations associated with health problems in workers. Conclusions: The results of the literature study found no significant association in cancer occurrence based on the length of PFOS exposure in workers. The literature search results also found no direct association between PFOS exposure to possible health problems.
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Grosshandler, W., C. Presser, D. Lowe, and W. Rinkinen. "Assessing Halon Alternatives for Aircraft Engine Nacelle Fire Suppression." Journal of Heat Transfer 117, no. 2 (May 1, 1995): 489–94. http://dx.doi.org/10.1115/1.2822548.
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A coaxial turbulent spray burner was built to evaluate the relative effectiveness of different chemicals for suppressing fires in a jet engine nacelle. The fire suppressant of current choice, halon 1301 (CF3Br), must be replaced because of its detrimental effect on the ozone layer. The alternatives being considered lack the chemical activity of CF3Br, so that the ability of the agents to mix into the flame convectively and to absorb heat is critical to their success. An agent delivery system was designed to inject the desired amount of material into the air upstream of a fuel nozzle and to control the agent injection rate through variation of the storage pressure and the duration of time that a solenoid valve remains open. The influence of air velocity, fuel flow, and injection period on the amount of nitrogen required to extinguish a jet fuel spray flame is discussed. The effectiveness of eleven different fluorocarbons, hydrofluorocarbons, and hydrochlorofluorocarbons is compared to that of halon 1301. The alternatives required 1.7 to 2.3 times the amount (on a mass basis) of CF3Br to extinguish the spray flame, with HCFC-22 being the most efficient and FC-31-10 the least.
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Gavriilidis, Asterios, Achilleas Constantinou, Klaus Hellgardt, King Kuok (Mimi) Hii, Graham J. Hutchings, Gemma L. Brett, Simon Kuhn, and Stephen P. Marsden. "Aerobic oxidations in flow: opportunities for the fine chemicals and pharmaceuticals industries." Reaction Chemistry & Engineering 1, no. 6 (2016): 595–612. http://dx.doi.org/10.1039/c6re00155f.
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This collaborative review (between teams of chemists and chemical engineers) describes the current scientific and operational hurdles that prevent the utilisation of aerobic oxidation reactions for the production of speciality chemicals and active pharmaceutical ingredients (APIs).
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Samuel, J. Jensen, and A. Ramesh. "Transient prediction capabilities of a novel physics-based ignition delay model in multi-pulsed direct injection diesel engines." International Journal of Engine Research 21, no. 6 (August 15, 2019): 948–65. http://dx.doi.org/10.1177/1468087419866590.
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This work is an extension of a novel physics-based ignition delay modeling methodology previously developed by the authors to predict physical and chemical ignition delays of multiple injections during steady operations in diesel engines. The modeling methodology is refined in this work to consider the influence of additional operating parameters such as volumetric efficiency, exhaust temperature and pressure on the ignition delay of multiple injections. Computational fluid dynamics predictions on two different engines indicated that the main spray encounters local temperatures about 60 K above average temperatures for about 1 mg of pilot. Hence, the modeling methodology was further refined to include this effect by considering the air mass trapped in pilot spray, computed based on the spray penetration and cone angle and tuned using results of the computational fluid dynamics studies. Comparisons of the ignition delay predictions with the stock boost temperature sensor and a specially incorporated, transient-capable fine wire thermocouple indicated that the measurements with stock sensor could be satisfactorily used for transients. Cycle-by-cycle changes in ignition delay could be predicted accurately when transients were imposed in boost pressure, rail pressure and main injection quantity in a turbocharged intercooled diesel engine controlled with an open engine control unit. Further validations were done even under a transient cycle when the engine was controlled by its stock engine control unit. The same tuning constants could be used for the prediction of the ignition delay under transients on another naturally aspirated engine. This indicates the suitability of the model for application in different engines. Finally, the model was incorporated within an open engine controller, and cycle-by-cycle prediction of ignition delays of the pilot and main injections were done in real time. It was possible to compute the ignition delays in less than 2 ms within engine control unit using the already available sensor inputs within an error band of ±60 µs.
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Konoplev, V., A. Zhukov, Z. Melnikov, and V. Sarbaev. "Research into the physical and chemical properties of fire-retardant materials of structural elements of trucks running on gas engine fuel with the aim of increasing their fire-retardant efficiency." Journal of Physics: Conference Series 2061, no. 1 (October 1, 2021): 012098. http://dx.doi.org/10.1088/1742-6596/2061/1/012098.
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Abstract The fire load is an integral part of the fire hazard definition. Reducing this load is one of directions to fight fires in transport. To study the physicochemical processes and thermal effects occurring as a result of thermal decomposition of wood fire-proofed by retardants like BAN, OK-GF, OK-DS (OK-GFM), SPAD-0 and their chemical compositions, we used the methods of differential thermal analysis, thermogravimetry, and derivative thermogravimetry. In addition, to study the intensity of physicochemical combustion processes, tests to control changes in woodwork masses and temperature at the top of pipe depending on the duration of combustion of the samples and the consumption of fire retardants were conducted. Fire retardant compositions like OK-GF, OK-DS, Pirilax biopyrene at the consumption of 0.1 kg / m2 ensure flame and combustion resistance of the wood. The analysis of the research results confirmed the possibility of assigning to wood structures of a lorry’s body of the group 1 of flame and combustion resistance. Using the above fire retardants and their compositions in the treatment of lodgment elements and runners significantly affects the possibility and duration of the combustion process of a lorry. This was tested by means of an artificial fire source method (without chemical treatment, the burning time does not exceed 50 minutes). This significantly improves post-collision safety of vehicles with an increased fire load in terms of fire resistance because of using the natural gas as a motor fuel.
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Dmitrichenko, M., A. Savchuk, Yu Turitsa, and A. Milanenko. "Influence of filter elements on the operation of tribomechanical systems." Problems of tribology 101, no. 3 (September 30, 2021): 56–62. http://dx.doi.org/10.31891/2079-1372-2021-101-3-56-62.
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Oil filter is a part of a gasoline or diesel engine lubrication system designed to clean the engine oil. Depending on where it is installed, the oil filtration system, they are divided into three types: - through-flow filter, which passes through all the oil that the pump feeds into the engine. A pressure regulating by-pass valve is installed upstream of the filter to protect the gaskets with oil seals. If the filter element is too dirty, the valve directs oil flow past the filter, preventing oil starvation of the bearings. Keeps engine from failing due to lack of lubrication; - a partial-flow filter is mounted parallel to the main oil line and cleans only a portion of the oil that enters the engine. Gradually the whole volume of oil passes through the filter element, giving a fairly high cleaning efficiency. However, this method does not provide absolute protection of parts from chips and other abrasives; - the combination filter combines a full-flow and a partial-flow cleaning principle. It consists of two filter elements, one mounted parallel to the oil line and the other cut into it. This ensures maximum cleaning efficiency and long filter life. The filter elements are divided into two types according to their efficiency in removing fine impurities: coarse filters, which remove coarse impurities, and fine filters, which remove fine impurities. According to the design of the housing and the possibility of replacing the filter element, filters are divided into multiple (collapsible) and disposable (non-collapsible). Modern engines may use filters in the form of a cartridge, which is inserted into a special compartment. During operation, the oil is first routed to the filter and then through the oil channels to the interacting parts in the engine. This principle is used on all standard passenger cars. A settling filter (gravity filter) is a tank with a filter element and a settling tank in which impurities are deposited by gravity. The centrifugal filter operates similarly to the gravity filter, only dirt settles in it under the action of centrifugal force resulting from the rotation of the body
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Nemchinov, S. G., V. A. Harevskiy, Yu I. Gorban, and S. G. Tsarichenko. "https://www.btpnadzor.ru/archive/protivopozharnaya-zashchita-mashinnykh-zalov-atomnykh-elektrostantsiy-s-ispolzovaniem-mnogofunktsionalnykh-robototekhnicheskikh-kompleksov." Occupational Safety in Industry, no. 2 (February 2022): 20–26. http://dx.doi.org/10.24000/0409-2961-2022-2-20-26.
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The problematic issues of the organization of fire extinguishing process in the engine rooms of nuclear power plants are considered. The need of prompt response to the occurrence of combustion source at the initial stage is substantiated. With the existing methods of ensuring fire safety, it is not always possible to achieve this goal. A conceptual approach is proposed concerning the construction of a system using robotic fire extinguishing installations, the hardware-software control complex of which allows to prevent the development of a fire. This is ensured by monitoring and analysis of the facility state, development of the control commands for the multifunctional fire protection complex. The innovative system for monitoring fire situation and fire extinguishing was created, which adapts in accordance with the dynamics of the development of a fire and a change in the situation. It is based on the software and digital solutions for ensuring comprehensive full-scale protection of the facilities from fires, accidents, and explosions. The risks to the life and health of the facility personnel and firefighters involved in extinguishing were minimized due to the absence of exposure to hazardous fire factors and their consequences. As a result, an unacceptable economic damage is prevented in case of fires and emergencies at the protected objects. Proposed complex with separate systems included in it differs from the traditional methods of fire protection. It is fully adapted to the likely scenarios for the development of the situation at the facility. As a result, the fire protection system is formed, which is based not on the general requirements (standards), but on the realistically possible emergency events. This approach not only ensures the efficiency of fire detection and elimination, but also reduces the cost of equipment operation.
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Yao, Lan, Sui Huai Yu, and Chao Jiang. "Research on Fire Engine Layout Design Based on System Analysis and Equipment Correlation." Applied Mechanics and Materials 271-272 (December 2012): 1100–1104. http://dx.doi.org/10.4028/www.scientific.net/amm.271-272.1100.
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Reasonable and scientific equipment layout design can adequately use the interior space to arrange and divide vehicle equipments, and the practical operation can be convenient, quick and safe. Take the anti-chemical fire engine as an example, the systems analysis method of vehicle equipment layout design especially for fire engine was proposed, and the correlation matrix and net were established according to the correlation table method in order to make sure the importance degree of equipments. Finally, three design options are evaluated, and the result proves that this method is a feasible solution.
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Kim, Min-Kyeong, Duckshin Park, Minjeong Kim, Jaeseok Heo, Sechan Park, and Hwansoo Chong. "The Characteristics and Distribution of Chemical Components in Particulate Matter Emissions from Diesel Locomotives." Atmosphere 12, no. 1 (January 5, 2021): 70. http://dx.doi.org/10.3390/atmos12010070.
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The use of diesel locomotives in transport is gradually decreasing due to electrification and the introduction of high-speed electric rails. However, in Korea, up to 30% of passenger and cargo transport still relies on diesel locomotives and vehicles. Many studies have shown that the exhaust gas from diesel locomotives poses a threat to human health. This study examined the characteristics of particulate matter (PM) in diesel locomotive engine exhaust. In a previous study, PM emissions were found to increase as the throttle was moved to a higher notch. The use of a portable emission measurement system (PEMS) in this study did not detect the highest emissions at notch 5, as is commonly found in gravimetric analyses. When comparing the mass concentrations, the notch 1 and 5 results were similar. However, at notch 8, there was a large difference between the mass concentrations collected on the filters. Further, to reduce the fine PM emitted from diesel locomotives, the ionic components, which account for the largest proportion of the total materials in fine PM, should be clearly identified. Therefore, in this study, an analysis of the weight, ionic composition, and metal components of fine PM discharged from a diesel locomotive was performed. Based on the results, Na+ (31%), Ca2+ (27%), NO3− (24%), and SO42− (13%), were the main ionic components, and the most abundant metal components being Ca (45%) and S (20%). In this study, the chemical components generated in diesel engines of other sources were compared, and as a result, different results were shown depending on the engine load and material ingredients. For the first time, a PEMS was used to measure PM from diesel vehicles, and a comparison was made with the results obtained by a gravimetric method. This is the first report of measuring PM concentrations by connecting a PEMS to a diesel locomotive, and of the distribution and characteristics of ions and heavy metals contained in the particles collected in the filter analyzed. The results indicate the importance of identifying the characteristics of fine PM emitted from a diesel locomotive and establishing an effective reduction measurement.
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D’Amato, Marco, Annarita Viggiano, and Vinicio Magi. "On the Turbulence-Chemistry Interaction of an HCCI Combustion Engine." Energies 13, no. 22 (November 11, 2020): 5876. http://dx.doi.org/10.3390/en13225876.
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A numerical study was carried out to evaluate the influence of engine combustion chamber geometry and operating conditions on the performance and emissions of a homogeneous charge compression ignition (HCCI) engine. Combustion in an HCCI engine is a very complex phenomenon that is influenced by several factors that need to be controlled, such as gas temperature, heat transfer, turbulence and auto-ignition of the gas mixture. An eddy dissipation concept (EDC) combustion model was used to take into account the interaction between turbulence and chemistry. The model assumed that reactions occur in small turbulent structures called fine-scales, whose characteristic lengths and times depend mainly on the turbulence level. The model parameters were slightly modified with respect to the standard model proposed by Magnussen, to correctly simulate the characteristics of the HCCI combustion process. A reduced iso-octane chemical mechanism with 186 species and 914 chemical reactions was employed together with a sub-mechanism for NOx. The model was validated by comparing the results with available experimental data in terms of pressure and instantaneous heat release rate. Two engine chamber geometries with and without a cavity in the piston were considered, respectively. The two engines provided significant differences in terms of fluid-dynamic patterns and turbulence intensity levels in the combustion chamber. The results show that combustion started earlier and proceeded faster for the flat piston, leading to an increase in both the peak pressure and gross indicated mean effective pressure, as well as a reduction of CO and UHC emissions. An additional analysis was performed by considering a case without swirl for the flat-piston case. Such an analysis shows that the swirl motion reduces the time duration of combustion and slightly increases the gross indicated work per cycle.
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Vikovich, Igor, Roman Zinko, Mar'yan Lavrovsky, and Andriy Polyakov. "Experimental studies of adapted medium-duty fire trucks for emergency response." Journal of Mechanical Engineering and Transport 12, no. 2 (February 2021): 25–33. http://dx.doi.org/10.31649/2413-4503-2020-12-2-25-33.
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Fire trucks should be maximally adapted to the elimination of emergency situations, in particular, to provide the necessary intensity of supply of extinguishing agents, that is, to be multifunctional. Special requirements are imposed on fire-fighting vehicles: high cross-country ability and speed, the ability to transport one compartment, transport tools and equipment for grabbing, backfilling with soil, filling the edge of the fire with water or chemical solutions, and the like. Scientific research is aimed at developing ways to assess the effectiveness of new models of fire and rescue vehicles for compliance with the requirements of the Ministry of Emergency Situations of Ukraine, in particular, through comparative analysis with alternative samples, to determine the factors affecting the operation of a fire truck, to develop a method for adapting vehicles for emergency response, to improve their level of operational excellence and operational efficiency. To realize the purpose of the assessment tests, a test procedure was developed and an experimental model of a fire-fighting vehicle for emergency response was created. The obtained relationship between the number of revolutions of the crankshaft of the engine and the value of the dynamic torque in the transmission of the test fire vehicle in the case of a sharp engagement of the clutch in the vehicle starting modes can be represented graphically. It is proposed to compare different variants of fire engine designs to take this characteristic as an efficiency criterion. Experimental studies were carried out: starting a car from a place on a steep rise, followed by an increase in gears; overcoming a roadside ditch with flat walls 0.2–0.6 m deep and at an angle of 45° to its axis; running over with wheels of one side of a fire engine on a curb 140–150 mm high; entering a turn from straight-line movement to the minimum possible turning radius on an asphalt surface in II and III gears at a constant speed of 10-12 km/h. To confirm the validity of the accepted assumptions of the mathematical model, the accuracy of applications and the reliability of the results obtained, the adequacy of mathematical modeling was checked by comparing the test problems of statics and dynamics of the movement of fire trucks for emergency response. A fire truck for liquidation of emergency situations, modeled on the basis of the proposed adaptation method of the base chassis for the needs of extinguishing forest fires and the formation of a container module, makes it possible to increase the efficiency of its use according to the selected criteria by 18%. The use of the longitudinal flexibility of the container modules in comparison with the conventional body mount provides a reduction in fuel consumption when driving a fire truck up to 4%.
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Law, Margaret. "What is a Fire Engineer?" Journal of Applied Fire Science 1, no. 1 (January 1, 1990): 3–6. http://dx.doi.org/10.2190/ec9u-wdca-9gp3-mpla.
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Timoshenko, V. I., L. K. Patryliak, Yu V. Knyshenko, V. M. Durachenko, and A. S. Dolinkevych. "Use of a “green” propellant in low-thrust control jet engine systems." Technical mechanics 2021, no. 4 (December 7, 2021): 29–43. http://dx.doi.org/10.15407/itm2021.04.029.
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The aim of this work is to analyze the state of the art in the development and use of pollution-free (“green”) propellants in low-thrust jet engines used as actuators of spacecraft stabilization and flight control systems and to adapt computational methods to the determination of “green”-propellant engine thrust characteristics. The monopropellant that is now widely used in the above-mentioned engines is hydrazine, whose decomposition produces a jet thrust due to the gaseous reaction products flowing out of a supersonic nozzle. Because of the high toxicity of hydrazine and the complex technology of hydrazine filling, it is important to search for its less toxic substitutes that would compare well with it in energy and mass characteristics. A promising line of this substitution is the use of ion liquids classed with “green” ones. The main components of these propellants are a water solution of an ion liquid and a fuel component. The exothermic thermocatalytic decomposition of a “green” propellant is combined with the combustion of its fuel component and increases the combustion chamber pressure due to the formation of gaseous products, which produces an engine thrust. It is well known that a “green” propellant itself and the products of its decomposition and combustion are far less toxic that hydrazine and the products of its decomposition, The paper presents data on foreign developments of “green” propellants of different types, which are under test in ground (bench) conditions and on a number of spacecraft. The key parameter that governs the efficiency of the jet propulsion system thrust characteristics is the performance of the decomposition and combustion products, which depends on their temperature and chemical composition. The use of equilibrium high-temperature process calculation methods for this purpose is too idealized and calls for experimental verification. Besides, a substantial contribution to the end effect is made by the design features of propellant feed and flow through a fine-dispersed catalyst layer aimed at maximizing the monopropellant-catalyst contact area. As a result, in addition to the computational determination of the thrust characteristics of a propulsion system under design, its experimental tryout is mandatory. The literature gives information on the performance data of “green”-propellant propulsion systems for single engines. However, in spacecraft control engine systems their number may amount to 8–16; in addition, they operate in different regimes and may differ in thrust/throttling characteristics, which leads to unstable propellant feed to operating engines. To predict these processes, the paper suggests a mathematical model developed at the Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine and adapted to “green”-propellant engine systems. The model serves to calculate the operation of low-thrust jet engine systems and describes the propellant flow in propellant feed lines, propellant valves, and combustion chambers. To implement the model, use was made of the results of experimental studies on a prototype “green”-propellant engine developed at Yuzhnoye State Design Office. The analysis of the experimental results made it possible to refine the performance parameters of the monopropellant employed and obtain computational data that may be used in analyzing the operation of a single engine or an engine system on this propellant type in ground and flight conditions
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Smelkov, G. I., V. A. Pekhotikov, A. I. Ryabikov, and A. A. Nazarov. "Updating of the National Normative Base in the Field of Ensuring Fire Safety of Electrical Wiring." Occupational Safety in Industry, no. 11 (November 2020): 29–36. http://dx.doi.org/10.24000/0409-2961-2020-11-29-36.
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In Russia every year, according to the statistics, the most fire hazardous types of electrical installations are electrical wiring, from which 65 % of fires occurred in 2019, associated with all the types of electrical installations. Considering the urgency of the problem, the Federal Research Budgetary Institution of the All-Russian Order of the Badge of Honor, the Research Institute of Fire Defense pays constant attention to increasing the level of fire prevention studies. One of the most important tasks in the institute activities in this Проблемы, суждения 35Безопасность Труда в Промышленности • Occupational Safety in Industry • № 11'2020 • www.safety.ru field is the development, updating, modification and harmonization of the national normative base regulating fire safety requirements and methods for assessing the fire safety of electrical installations, and, above all, of course, electrical wiring. The fundamental regulatory documents are the Technical Regulations TR EEU 043/2017 and the Federal Law of 22. 07. 2008 № 123-FZ «Technical regulations on fire safety requirements», in the development of the electrical section of which the authors of the article took an active part. Particular attention here deserves Clause 2 of Article 82, which regulates the requirements for fire resistance (operability) of cable lines and electrical wiring systems for fire protection of the objects under fire conditions, and Сlause 8 of the same article, which imposes the requirements that were awaited for a long time by all the branches of industry, agriculture, housing construction and, first of all, of course, power engineers and employees of the fire service: «Cables laid openly must be flame retardant». The requirement applies to all the objects, regardless of their functional fire hazard. Over the past three years, the Institute carried out a large scientific research and rule-making work on the revision, development and substantiation of the proposed solutions for new editions of the interstate standards for various types of electrical wiring using: molded electrical wiring products, cables of increased fire resistance under fire conditions, fire retardant cable coatings and cable penetrations. In theoretical terms, the interest is in the proposed by the authors a calculation method for assessment of electrical products fire hazard, based on the stochasticity of emergency modes that cause their failure and ignition.
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Al-Naiema, Ibrahim M., Anusha P. S. Hettiyadura, Henry W. Wallace, Nancy P. Sanchez, Carter J. Madler, Basak Karakurt Cevik, Alexander A. T. Bui, Josh Kettler, Robert J. Griffin, and Elizabeth A. Stone. "Source apportionment of fine particulate matter in Houston, Texas: insights to secondary organic aerosols." Atmospheric Chemistry and Physics 18, no. 21 (October 30, 2018): 15601–22. http://dx.doi.org/10.5194/acp-18-15601-2018.
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Abstract. Online and offline measurements of ambient particulate matter (PM) near the urban and industrial Houston Ship Channel in Houston, Texas, USA, during May 2015 were utilized to characterize its chemical composition and to evaluate the relative contributions of primary, secondary, biogenic, and anthropogenic sources. Aerosol mass spectrometry (AMS) on nonrefractory PM1 (PM ≤ 1 µm) indicated major contributions from sulfate (averaging 50 % by mass), organic aerosol (OA, 40 %), and ammonium (14 %). Positive matrix factorization (PMF) of AMS data categorized OA on average as 22 % hydrocarbon-like organic aerosol (HOA), 29 % cooking-influenced less-oxidized oxygenated organic aerosol (CI-LO-OOA), and 48 % more-oxidized oxygenated organic aerosol (MO-OOA), with the latter two sources indicative of secondary organic aerosol (SOA). Chemical analysis of PM2.5 (PM ≤ 2.5 µm) filter samples agreed that organic matter (35 %) and sulfate (21 %) were the most abundant components. Organic speciation of PM2.5 organic carbon (OC) focused on molecular markers of primary sources and SOA tracers derived from biogenic and anthropogenic volatile organic compounds (VOCs). The sources of PM2.5 OC were estimated using molecular marker-based positive matric factorization (MM-PMF) and chemical mass balance (CMB) models. MM-PMF resolved nine factors that were identified as diesel engines (11.5 %), gasoline engines (24.3 %), nontailpipe vehicle emissions (11.1 %), ship emissions (2.2 %), cooking (1.0 %), biomass burning (BB, 10.6 %), isoprene SOA (11.0 %), high-NOx anthropogenic SOA (6.6 %), and low-NOx anthropogenic SOA (21.7 %). Using available source profiles, CMB apportioned 41 % of OC to primary fossil sources (gasoline engines, diesel engines, and ship emissions), 5 % to BB, 15 % to SOA (including 7.4 % biogenic and 7.6 % anthropogenic), and 39 % to other sources that were not included in the model and are expected to be secondary. This study presents the first application of in situ AMS-PMF, MM-PMF, and CMB for OC source apportionment and the integration of these methods to evaluate the relative roles of biogenic, anthropogenic, and BB-SOA. The three source apportionment models agreed that ∼ 50 % of OC is associated with primary emissions from fossil fuel use, particularly motor vehicles. Differences among the models reflect their ability to resolve sources based upon the input chemical measurements, with molecular marker-based methods providing greater source specificity and resolution for minor sources. By combining results from MM-PMF and CMB, BB was estimated to contribute 11 % of OC, with 5 % primary emissions and 6 % BB-SOA. SOA was dominantly anthropogenic (28 %) rather than biogenic (11 %) or BB-derived. The three-model approach demonstrates significant contributions of anthropogenic SOA to fine PM. More broadly, the findings and methodologies presented herein can be used to advance local and regional understanding of anthropogenic contributions to SOA.
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Tsekenis, Stylianos-Alexios, Kumara Gurubaran Ramaswamy, Nigel Tait, Yannis Hardalupas, Alexander Taylor, and Hugh McCann. "Chemical species tomographic imaging of the vapour fuel distribution in a compression-ignition engine." International Journal of Engine Research 19, no. 7 (September 11, 2017): 718–31. http://dx.doi.org/10.1177/1468087417730214.
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This article reports the first application of chemical species tomography to visualise the in-cylinder fuel vapour concentration distribution during the mixing process in a compression-ignition engine. The engine was operated in motored conditions using nitrogen aspiration and fired conditions using a gasoline-like blend of 50% iso-dodecane and 50% n-dodecane. The tomography system comprises 31 laser beams arranged in a co-planar grid located below the injector. A novel, robust data referencing scheme was employed to condition the acquired data for image reconstruction using the iterative Landweber algorithm. Tomographic images were acquired during the compression stroke at a rate of 13 frames per crank angle degree within the same engine cycle at 1200 r min−1. The temperature-dependent fuel evaporation rate and mixing evolution were observed at different injection timings and intake pressure and temperature conditions. An initial cross-validation of the tomographic images was performed with planar laser-induced fluorescence images, showing good agreement in feature localisation and identification. This is the first time chemical species tomography using near-infrared spectroscopic absorption has been validated under engine conditions, and the first application of chemical species tomography to a compression-ignition engine.
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Ognjanovic, Nevena, Slobodan Petrovic, Dejan Bezbradica, and Zorica Knezevic-Jugovic. "Lipases as biocatalysts for biodiesel production." Chemical Industry 64, no. 1 (2010): 1–8. http://dx.doi.org/10.2298/hemind1001001o.
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Lipases can be used for a variety of biotechnological applications: synthesis of fine chemicals, therapeutics, agrochemicals, cosmetics, flavors, biopolymers and biodiesel. Biodiesel is an alternative fuel for diesel engines that is environmentally acceptable. Conventionally, biodiesel is produced by transesterification of triglycerides and short chain alcohols in the presence of an acid or an alkaline catalyst. There are several problems associated with this kind of production that can be resolved by using lipase as the biocatalyst. The usage of lipases has several advantages over the conventional chemical methods. It is considered as less energy intensive and environmentally friendly. However, there are two main obstacles associated with the effective utilization of lipases in the production of biodiesel. The main one is the cost of the enzyme and its poor stability in the presence of excess alcohol. Several strategies are proposed to overcome these drawbacks: immobilization of lipases, stepwise addition of alcohol, and the usage of novel acyl acceptors and the usage of whole cell biocatalysts.
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Giurcan, Venera, Codina Movileanu, Adina Magdalena Musuc, and Maria Mitu. "Laminar Burning Velocity of Biogas-Containing Mixtures. A Literature Review." Processes 9, no. 6 (June 4, 2021): 996. http://dx.doi.org/10.3390/pr9060996.
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Currently, the use of fossil fuels is very high and existing nature reserves are rapidly depleted. Therefore, researchers are turning their attention to find renewable fuels that have a low impact on the environment, to replace these fossil fuels. Biogas is a low-cost alternative, sustainable, renewable fuel existing worldwide. It can be produced by decomposition of vegetation or waste products of human and animal biological activity. This process is performed by microorganisms (such as methanogens and sulfate-reducing bacteria) by anaerobic digestion. Biogas can serve as a basis for heat and electricity production used for domestic heating and cooking. It can be also used to feed internal combustion engines, gas turbines, fuel cells, or cogeneration systems. In this paper, a comprehensive literature study regarding the laminar burning velocity of biogas-containing mixtures is presented. This study aims to characterize the use of biogas as IC (internal combustion) engine fuel, and to develop efficient safety recommendations and to predict and reduce the risk of fires and accidental explosions caused by biogas.
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Omer, Muhammad I., and Dilshad K. Jaf. "Evaluation of Concrete Quality for Reinforced Concrete Frame Members Exposed to Natural Fires at Early Ages Using in situ Test Methods." Open Civil Engineering Journal 13, no. 1 (December 31, 2019): 201–9. http://dx.doi.org/10.2174/1874149501913010201.
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Background: In recent years, numerous reinforced concrete buildings have been constructed in Iraq and some developing countries. Fire accidents occur in wooden formwork especially during the summer season due to problems associated with the construction procedure and on-site management. And fires can erupt during the construction stage of buildings. Introduction: Generally, if fire accidents occur in a wooden formwork, in these situations the concrete in the field is at an early age (i.e., “young”). The internal structure and chemical composition of early-age concrete are different from that of the carrier due to incomplete hydration at an early age. This study aimed to evaluate the strength of reinforced concrete frames at early ages when exposed to natural fire. The evaluation of existing buildings is an important issue that involves researchers and engineers in many countries. Methods: The experimental program consisted of constructing three full-scale reinforced concrete frames that are then exposed to natural fire. When the concrete age reaches three and five days by firing its formwork, the concrete quality of the structure was evaluated via ultrasonic pulse velocity as a nondestructive measurement. Core test was used as a destructive technique to implement a relationship between compressive strength and nondestructive measurements Results: The results showed that the frame exposed to natural fire early was generally more affected than the other frame, and its compressive strength was reduced close to 33%. The results also showed that the ultrasonic pulse velocity test for the structural elements was smaller than those of the core test Conclusion: It can be concluded that the current assessment methodology must be evaluated to provide practical suggestions that can enhance the reliability of assessing the in situ strength of existing concrete structures by nondestructive tests and cores.
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Wang, Qian, Xiao Jing Han, Ping Qi, and Jing Wang. "Simulation of Urea-SCR Catalytic Converter for Diesel Engine." Advanced Materials Research 354-355 (October 2011): 513–17. http://dx.doi.org/10.4028/www.scientific.net/amr.354-355.513.
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A three-dimensional model of a diesel Urea-SCR（Selective Catalytic Reduction）catalytic converter system was set up with aid of CFD software AVL FIRE coupled with available knowledge of SCR chemical reaction kinetics. Basing on the validation of the spray injection model of Urea-water-solution, the numerical simulation was made to get the distribution of pressure, velocity, temperature and species concentration in the converter and NOxconversion in different conditions by considering the injection and evaporation of the urea-water-solution, the thermal decomposition and hydrolysis into ammonia and the surface catalytic reactions in the monolith. The simulated results have some reference meaning for improving NOxconversion efficiency and optimizing the diesel SCR catalytic converter.
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Tiwari, Shashank S., Shivkumar Bale, Diptendu Das, Arpit Tripathi, Ankit Tripathi, Pawan Kumar Mishra, Adam Ekielski, and Sundaramurthy Suresh. "Numerical Simulations of a Postulated Methanol Pool Fire Scenario in a Ventilated Enclosure Using a Coupled FVM-FEM Approach." Processes 10, no. 5 (May 6, 2022): 918. http://dx.doi.org/10.3390/pr10050918.
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Numerical investigations have been carried out for a postulated enclosure fire scenario instigated due to methanol pool ignition in a chemical cleaning facility. The pool fire under consideration is radiation-dominated and poses a risk to the nearby objects if appropriate safety requirements are not met. The objective of the current study was to numerically evaluate the postulated fire scenario and provide safety recommendations to prevent/minimize the hazard. To do this, the fire scenario was first modeled using the finite volume method (FVM) based solver to predict the fire characteristics and the resulting changes inside the enclosure. The FDS predicted temperatures were then used as input boundary conditions to conduct a three-dimensional heat transfer analysis using the finite element method (FEM). The coupled FVM–FEM simulation approach enabled detailed three-dimensional conjugate heat transfer analysis. The proposed FVM–FEM coupled approach to analyze the fire dynamics and heat transfer will be helpful to safety engineers in carrying out a more robust and reliable fire risk assessment.
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Cho, Hee-joo, Joonwoo Kim, Nohhyeon Kwak, Heesung Kwak, Taewan Son, Donggeun Lee, and Kihong Park. "Application of Single-Particle Mass Spectrometer to Obtain Chemical Signatures of Various Combustion Aerosols." International Journal of Environmental Research and Public Health 18, no. 21 (November 4, 2021): 11580. http://dx.doi.org/10.3390/ijerph182111580.
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A single-particle mass spectrometer (SPMS) with laser ionization was constructed to determine the chemical composition of single particles in real time. The technique was evaluated using various polystyrene latex particles with different sizes (125 nm, 300 nm, 700 nm, and 1000 nm); NaCl, KCl, MgCO3, CaCO3, and Al2O3 particles with different chemical compositions; an internal mixture of NaCl and KCl; and an internal mixture of NaCl, KCl, and MgCl2 with different mixing states. The results show that the SPMS can be useful for the determination of chemical characteristics and mixing states of single particles in real time. The SPMS was then applied to obtain the chemical signatures of various combustion aerosols (diesel engine exhaust, biomass burning (rice straw), coal burning, and cooking (pork)) based on their single-particle mass spectra. Elemental carbon (EC)-rich and EC-organic carbon (OC) particles were the predominant particle types identified in diesel engine exhaust, while K-rich and EC-OC-K particles were observed among rice straw burning emissions. Only one particle type (ash-rich particles) was detected among coal burning emissions. EC-rich and EC-OC particles were observed among pork burning particles. The single-particle mass spectra of the EC or OC types of particles differed among various combustion sources. The observed chemical signatures could be useful for rapidly identifying sources of atmospheric fine particles. In addition, the detected chemical signatures of the fine particles may be used to estimate their toxicity and to better understand their effects on human health.
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Illarionov, Anatoliy G., Stepan I. Stepanov, Inna A. Naschetnikova, Artemiy A. Popov, Prasanth Soundappan, K. H. Thulasi Raman, and Satyam Suwas. "A Review—Additive Manufacturing of Intermetallic Alloys Based on Orthorhombic Titanium Aluminide Ti2AlNb." Materials 16, no. 3 (January 20, 2023): 991. http://dx.doi.org/10.3390/ma16030991.
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Titanium alloys based on orthorhombic titanium aluminide Ti2AlNb are promising refractory materials for aircraft engine parts in the operating temperature range from 600–700 °C. Parts made of Ti2AlNb-based alloys by traditional technologies, such as casting and metal forming, have not yet found wide application due to the sensitivity of processability and mechanical properties in chemical composition and microstructure compared with commercial solid-solution-based titanium alloys. In the last three decades, metal additive manufacturing (MAM) has attracted the attention of scientists and engineers for the production of intermetallic alloys based on Ti2AlNb. This review summarizes the recent achievements in the production of O-phase-based Ti alloys using MAM, including the analysis of the feedstock materials, technological processes, machines, microstructure, phase composition and mechanical properties. Powder bed fusion (PBF) and direct energy deposition (DED) are the most widely employed MAM processes to produce O-phase alloys. MAM provides fully dense, fine-grained material with a superior combination of mechanical properties at room temperature. Further research on MAM for the production of critical parts made of Ti2AlNb-based alloys can be focused on a detailed study of the influence of post-processing and chemical composition on the formation of the structure and mechanical properties, including cyclic loading, fracture toughness, and creep resistance.
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Li, Y., K. O. Patten, D. J. Wuebbles, and D. Youn. "Potential impacts of CF<sub>3</sub>I on ozone as a replacement for CF<sub>3</sub>Br in aircraft applications." Atmospheric Chemistry and Physics Discussions 6, no. 3 (June 26, 2006): 5163–95. http://dx.doi.org/10.5194/acpd-6-5163-2006.
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Abstract. Iodotrifluoromethane (CF3I) has been considered to be a candidate replacement for bromotrifluoromethane (CF3Br), which is used in aircraft for fuel inerting and for fire fighting. In this study, the chemical effects of aircraft-released CF3I on atmospheric ozone were examined with the University of Illinois at Urbana-Champaign two-dimensional chemical-radiative-transport (UIUC 2-D CRT) model. Using an earlier estimate of the aircraft emission profile for tank inerting in military aircraft, the resulting equivalent Ozone Depletion Potentials (ODPs) for CF3I were in the range of 0.07 to 0.25. As a sensitivity study, we also analyzed CF3I emissions associated with fuel inerting if it were to occur at lower altitudes using an alternative estimate. The model calculations of resulting effects on ozone for this case gave ODPs≤0.05. Furthermore, through interactions with the National Institute of Standards and Technology (NIST), we analyzed the potential effects on ozone resulting from using CF3I in fire fighting connected with engine nacelle and auxiliary power unit applications. The scenarios evaluated using the NIST estimate suggested that the ODPs obtained by assuming aircraft flights occurring in several different latitude regions of the Northern Hemisphere are extremely low. According to the model calculation, the altitude where CF3I is released from aircraft is a dominant factor in its ozone depletion effects. On the assumption that the CF3I emission profile is representative of actual release characteristics, aircraft-released CF3I has much lower impacts on the ozone layer and can be a qualified substitute of CF3Br in engine nacelles.
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Maio, Giampaolo, Zhihao Ding, Karine Truffin, Olivier Colin, Olivier Benoit, and Stéphane Jay. "ECFM-LES modeling with AMR for the CCV prediction and analysis in lean-burn engines." Science and Technology for Energy Transition 77 (2022): 20. http://dx.doi.org/10.2516/stet/2022017.
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A Large-Eddy Simulation (LES) modeling framework, dedicated to ultra-lean spark-ignition engines, is proposed and validated in the present work. A direct injection research engine is retained as benchmark configuration. The LES model is initially validated using the cold gas-exchange conditions by comparing numerical results with PIV (Particle Imaging Velocimetry) experimental data. Then, the fired configuration is investigated, combining ECFM (Extended Coherent Flame Model) turbulent combustion model with Adaptive Mesh Refinement (AMR). The capability of the model to reproduce experimental pressure envelope and cycle-to-cycle variability is assessed. Within the major scope of the work, a particular focus on the Combustion Cyclic Variability (CCV) is made correlating them with the variability encountered in the in-cylinder aerodynamic variations. R3P4. Finally two post-processing tools, Empirical Mode Decomposition (EMD) and Γ3p function, are proposed and combined to analyse for the first time the aerodynamic tumble-based in-cylinder velocity field. Both tools make it possible to get deeply into the insight and visualization of the flow field and to understand the links between its cyclic variability and the combustion cyclic variability.
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Kapustin, F. L., and A. F. Kapustin. "Influence of Plasticizers on the Properties of Fine-Grained Polymer Concrete." Solid State Phenomena 299 (January 2020): 72–77. http://dx.doi.org/10.4028/www.scientific.net/ssp.299.72.
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Polymer concretes are used in construction, engineering, electrical and chemical industries. Polymer concrete mixes are characterized by low mobility mixtures, due to their high viscosity. It makes difficult to use them in the production of thin-walled and high-reinforced structures, monolithic floors, application of finishing and protective coatings and repairing of roads. The influence of additives of dibutyl-phthalate, chlorinated paraffin, technical glycerin and engine oil on the mobility of the concrete mix and the physical and mechanical properties of fine-grained concrete, based on polyester resin, was studied. For polymer concretes with different type and quantity of plasticizer the density and bending and compression strength were determined. To improve the workability of the concrete mix and obtain a polymer concrete with a homogeneous structure and high strength, it is recommended to use chlor-paraffin ChP-470A and “Lukoil” engine oil as a plasticizer.
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Putra, Muhlas Adi, Yuspian Gunawan, and La Hasanudin. "Analisis CPO, Asam Fosfat dan Soda Api Sebagai Pengganti Bahan Bakar Minyak (BBM) Mesin Diesel Dengan Variasi Campuran 98%, 1%, 1% Dan 95%, 2%, 3%, dan 95%, 3% 2% Mengunakan Pengujian Kalor." Enthalpy : Jurnal Ilmiah Mahasiswa Teknik Mesin 5, no. 4 (December 31, 2020): 94. http://dx.doi.org/10.55679/enthalpy.v5i4.15764.
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Energy needs continue to grow as the industry develops and the world's population grows. The growing need for fuel oil is causing fewer crude inventories. So we did research on Cpo Analysis, Phosphoric Acid And Fire Soda In Lieu of Fuel Oil (Fuel) Diesel Engines With Mixed Variations 98%, 1%, 1% And 95%, 2%, 3%, And 95%, 3% 2% Using Calorific Testing. Go to this study to find out the calorific value and combustion rate of the biodiesel ed. The results of the study in three biodiesel experiments that were most effective for use were shown in the trial to three CPO 95%, 3% posephuric acid and 2% fire soda with a combustion rate of 0.309 gr/min within 30.42 minutes with a final temperature of 57oC. In the three most effective biodiesel experiments to use, three CPO 95%, 3% asamposfat and 2% soda api witha calorific value of 8208.39 cal/gr with a final temperature of 57oC. In the manufacture of biodiesel that affects from the mixture of chemicals as much as soda fire will be better and the less phosphoric acid it will be good. Keywords: Biodiesel, Calorific Value, and Combustion Rate
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Zareei, Javad, José Ricardo Nuñez Alvarez, Yolanda Llosas Albuerne, María Rodríguez Gámez, and Ángel Rafael Arteaga Linzan. "A Simulation Study of the Effect of HCNG Fuel and Injector Hole Number along with a Variation of Fuel Injection Pressure in a Gasoline Engine Converted from Port Injection to Direct Injection." Processes 10, no. 11 (November 14, 2022): 2389. http://dx.doi.org/10.3390/pr10112389.
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The number of injector holes and the fuel-injection pressure in an internal combustion engine can affect engine performance and exhaust emissions. Conversion of a port-injection gasoline engine to an HCNG direct-injection engine improves engine performance and exhaust emissions. In addition, increasing the injection pressure helps to increase engine performance. In this study, AVL Fire software was used to perform simulation by certain adjustments. The injection pressure was applied in mods of 15, 20, and 25 bars, the injector holes numbers were 3 and 6, the compression ratio changed from 10:1 to 14:1, and the amount of hydrogen enrichment to natural gas was in mods of 10%, 20%, 30%, and 40%. This paper discusses the items above with regard to power, torque, combustion chamber pressure, fuel conversion efficiency, and exhaust emissions. The result determined that increasing the number of injector holes improves the performance engine and reduces CO emission so that the contour plots confirmed the balanced distribution of temperature and pressure. According to obtained results, maximum engine performance improved from 2.5% to 5% at different speeds and 30% added hydrogen, 25 bar injection pressure, and 6-hole injectors. The amount of CO decreased by approximately 30%, and NOx increased by about 10%.
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AO, Akinola, and Adeyinka TF. "Physicochemical Characteristics Study of Oil Extracted from Almond Seed." Saudi Journal of Engineering and Technology 7, no. 6 (July 6, 2022): 305–11. http://dx.doi.org/10.36348/sjet.2022.v07i06.005.
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The physicochemical properties of the extracted oil from almond seed were investigated. Physical properties such as cloud point, pour point, fire point, smoke point, specific gravity, refractive index, and viscosity; and the chemical properties such as acid value, free fatty acid, saponification value, iodine value, ester value, and peroxide value were investigated for both raw almond oil and transesterified almond oil. The various properties were investigated using ASTM standard methods and calculations. Results obtained for physical properties: cloud point, pour point, fire point, smoke point, specific gravity, refractive index, and kinematic viscosity were 〖-3〗^o C, 〖-9〗^o C, 〖220〗^o C, 〖130〗^o C, 0.928, 1.462, 21.84 〖mm〗^2/sec respectively for the transesterified almond oil. Result obtained for the chemical properties of the transesterified almond oil: acid value, free fatty acid, saponification value, iodine value 〖mgI〗_2/g, and ester value, values were determined to be: 2.05, 1.03, 79.71, 34.33, and 77.66. It was concluded that transesterified Almond oil have a great potential for use as fuel alternative and substitute for internal combustion engine with its high purity, low corrosion ability and ease of ignition.
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Hossain, Muhammad Monowar, Safat Al-Deen, Md Kamrul Hassan, Sukanta Kumer Shill, Md Abdul Kader, and Wayne Hutchison. "Mechanical and Thermal Properties of Hybrid Fibre-Reinforced Concrete Exposed to Recurrent High Temperature and Aviation Oil." Materials 14, no. 11 (May 21, 2021): 2725. http://dx.doi.org/10.3390/ma14112725.
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Over the years, leaked fluids from aircraft have caused severe deterioration of airfield pavement. The combined effect of hot exhaust from the auxiliary power unit of military aircraft and spilt aviation oils have caused rapid pavement spalling. If the disintegrated concreted pieces caused by spalling are sucked into the jet engine, they may cause catastrophic damage to the aircraft engine or physical injury to maintenance crews. This study investigates the effectiveness of incorporating hybrid fibres into ordinary concrete to improve the residual mechanical and thermal properties to prevent spalling damage of pavement. Three fibre-reinforced concrete samples were made with micro steel fibre and polyvinyl alcohol fibre with a fibre content of zero, 0.3%, 0.5% and 0.7% by volume fraction. These samples were exposed to recurring high temperatures and aviation oils. Tests were conducted to measure the effects of repeated exposure on the concrete’s mechanical, thermal and chemical characteristics. The results showed that polyvinyl alcohol fibre-, steel fibre- and hybrid fibre-reinforced concrete suffered a 52%, 40% and 26.23% of loss of initial the compressive strength after 60 cycles of exposure to the conditions. Moreover, due to the hybridisation of concrete, flexural strength and thermal conductivity was increased by 47% and 22%. Thus, hybrid fibre-reinforced concrete performed better in retaining higher residual properties and exhibited no spalling of concrete.
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Nourhani, Amir, Emil Karshalev, Fernando Soto, and Joseph Wang. "Multigear Bubble Propulsion of Transient Micromotors." Research 2020 (February 21, 2020): 1–9. http://dx.doi.org/10.34133/2020/7823615.
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Transient, chemically powered micromotors are promising biocompatible engines for microrobots. We propose a framework to investigate in detail the dynamics and the underlying mechanisms of bubble propulsion for transient chemically powered micromotors. Our observations on the variations of the micromotor active material and geometry over its lifetime, from initial activation to the final inactive state, indicate different bubble growth and ejection mechanisms that occur stochastically, resulting in time-varying micromotor velocity. We identify three processes of bubble growth and ejection, and in analogy with macroscopic multigear machines, we call each process a gear. Gear 1 refers to bubbles that grow on the micromotor surface before detachment while in Gear 2 bubbles hop out of the micromotor. Gear 3 is similar in nature to Gear 2, but the bubbles are too small to contribute to micromotor motion. We study the characteristics of these gears in terms of bubble size and ejection time, and how they contribute to micromotor displacement. The ability to tailor the shell polarity and hence the bubble growth and ejection and the surrounding fluid flow is demonstrated. Such understanding of the complex multigear bubble propulsion of transient chemical micromotors should guide their future design principles and serve for fine tuning the performance of these micromotors.
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Li, Xiao Long, Yang Wang, Tao Xu, Fei Yu Song, Ya Jun He, and Bin Hong. "The Simulation of Hydraulic Free Piston Engine Fueled with DME in HCCI Mode." Advanced Materials Research 602-604 (December 2012): 1090–94. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.1090.
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In order to investigate the performance of hydraulic free piston engine (HFPE) fueled with dimethyl-ether (DME) under homogeneous charge compression ignition (HCCI) combustion, one-dimensional and three-dimensional simulation models are established by AMESIM and FIRE respectively. The simulation results show that the piston’s velocity and the displacement are dissymmetric about top dead center (TDC). The residence time of piston around TDC is quite short. DME chemical reaction kinetic mechanism is applied to three-dimensional computational fluid dynamics (CFD) model. Under equivalence ratio of 0.4, boost ratio of 1.33 and EGR ratio of 0.4, three heat release peaks appears. Oxidation of CO which contributes 38% of total energy is considered as the main reason of the third heat release peak.
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Zhang, Yanhui, Yunhao Zhong, Jie Wang, Dongli Tan, Zhiqing Zhang, and Dayong Yang. "Effects of Different Biodiesel-Diesel Blend Fuel on Combustion and Emission Characteristics of a Diesel Engine." Processes 9, no. 11 (November 7, 2021): 1984. http://dx.doi.org/10.3390/pr9111984.
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In this paper, biodiesel was used as an alternative fuel to investigate the combustion and emission characteristics of a four-stroke diesel engine, in terms of cylinder pressure, heat release rate, cylinder temperature, brake thermal efficiency, brake specific fuel consumption, nitrogen oxide, soot, carbon monoxide, and hydrocarbon. Firstly, a diesel engine cylinder model was developed by AVL-Fire software coupled with CHEMKIN code to simulate the injection and combustion of biodiesel with a kinetic mechanism with 106 species and 263 reactions. Then, the simulation model was validated by experimental results under 100% and 50% load conditions and used to simulate the combustion process of a diesel engine fueled with pure diesel, biodiesel, and biodiesel–diesel blends with 10%, 20%, 30% biodiesel by volume, respectively. The results showed that the brake specific fuel consumption increased with the increase of mixed biodiesel ratio. The brake specific fuel consumptions of B10, B20 and B30 increased by 1.1%, 2.3% and 3.3%, respectively, compared with that of D100. The combustion and emission characteristics of the diesel engine are improved. Therefore, biodiesel can be used as an alternative fuel for the diesel engine. The diesel–biodiesel fuel can improve the combustion and emission characteristics of the diesel engine.
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Haiducu, Maria, Raluca-Aurora Ștepa, Iuliana-Pamela Scarlat, and Elena-Ruxandra Chiurtu. "Studies on the exposure of workers to fine particles from diesel engine exhaust emissions generated in urban transport." MATEC Web of Conferences 373 (2022): 00051. http://dx.doi.org/10.1051/matecconf/202237300051.
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The paper presents the results of the studies on the exposure of workers who may face exhaust emissions of diesel engines from urban transport. Many workers such as drivers, toll booth workers, security guards, public domain workers, police officers may be exposed daily to the chemical pollutants from urban transport. It is estimated that 52% of annual occupational deaths in the European Union can be attributed to work-related cancers. The study responds to the actions to prevent the exposure of workers to carcinogens that the European Commission has included in the Europe’s Beating Cancer Plan adopted in early 2021.
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Hashchuk, P., and S. Nikipchuk. "MODELING OF HEAT EXCHANGE PROCESSES EXPECTING IN CYLINDERS OF THE INTERNAL COMBUSTION ENGINES." Fire Safety, no. 33 (December 31, 2018): 15–34. http://dx.doi.org/10.32447/20786662.33.2018.03.
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The general principles of model reflection of working processes in the internal combustion engine are investigated. Like that intramolecular (chemically effective), molecular (thermodynamically active) or macroscopic (ordered by external manifestation) motion in substances causes mass transfer - diffusion, impulse transfer - viscosity, as well as they form the transfer of energy of disordered motion - heat-exchanging. By tying the phenomena of mass, momentum and energy transfer with molecular, intraocular and ordered motions, respectively, the leading, radial and convection components of each of these phenomena can be distinguished. Due to the common condition, diffusion, viscosity, heat transfer are interconnected phenomena and play a decisive role in processes passing through cylinders of the internal combustion engine. Therefore, they together should have been subject to some general harmonious theory of motion and energy exchange, which is based on the uniform physical and mathematical principles of environmental reflection. However, today such a theory does not exist. Because of this, in the study of heat exchange processes in the internal combustion engines we have to move, relying heavily on the principles of empiricism.
In spite of the extremely complex phenomenon of heat transfer, the internal combustion engine in the working space of the engine is such that it allows us to rely on relatively simple model descriptions based on the principles of empiricism.
The purpose of the work — based on the principles of the theory of similarity, to justify the possibility of adequate reflection and formalized generalization of experimentally identified information about the laws of the flow of heat transfer processes in the engines of Otto (the engine of rapid internal combustion).
The main object of empirical research is the coefficient of heat transfer. Only meaningful transparency and ease of use can be explained by the fact that so far this concept is widely used, although it is completely motivated can be replaced by a more general dimensionless characteristic. A great deal of empirical dependencies are proposed for calculating this coefficient. Each of them has own level of universality and it is applicability limits for adequacy. Generally, universality and adequacy are not mutually conductive characteristics of the quality of empirical relationships. That is why studying a certain set of engine operating modes, it is desirable to involve in the mathematical and experimental apparatus of research, such analytically displayed empirical relationships, which within this set remained unchanged by the structure and values of its main parameters.
Heat transfer in the cylinder of the engine of rapid internal combustion between the gas and the wall of the combustion space occurs mainly due to forced convection. Actually in the engine operating on the Otto cycle, the heat transfer as a result of radiation in the course of fueling is generally negligible because (unlike a diesel engine), in the projectile of combustion, there is not a significant amount of fired particles of soot, and by themselves, gases as emitters, as compared to forced turbulent convection, can tolerate a relatively small amount of heat, which is unlikely to be taken into consideration in general.
Equation of forced convection is traditionally based on a similarity relationship between criteria Nusselt (Nu), Reynolds (Re), Prandtl (Pr); C, n, m, — constant. G.Woschni found out that the values of the degrees of power are acceptable and .But in general it turned out that good simulation results can be obtained on the basis of experimental information on the flow of pressure and average temperature in the engine cylinder, taking and for each mode of operation of the engine its meaning from the range .Examples of model reproduction of the change in the coefficient of heat output from the angle of rotation of the motor shaft for different loads are given.
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Yang, Shi Gang, Ya Dong Zhang, and Hao Wu. "Comparison and Validation of Thermal Radiation Models for Hydrocarbon Jet Fire and Fireball." Applied Mechanics and Materials 204-208 (October 2012): 3503–12. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.3503.
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Primary consequences of fire hazards include personnel injuries, fatalities and/or facility and equipment damage due to high air temperatures, radiant heat fluxes or direct contact with flames. Many methods have been proposed to evaluate the thermal radiation incident on a target. This paper presents a survey of thermal models that can be used in quantitative consequence analysis and recommends a model that should be used to examine accident-related hazards. The capabilities of the existing conventional empirical models for estimating the incident thermal radiation from fireballs and jet fires were thoroughly evaluated by conducting several field trials. First, it was found that for estimating a fireball’s diameter, duration and surface emissive power in the downwind location, the TNO (The Netherlands Organization of Applied Scientific Research) model should be employed. Second, for estimating surface emissive power from fireballs in the crosswind location and incident thermal radiation power absorbed by the target located in the fireball’s diameter, the CCPS (Center for Chemical Process Safety of the American Institute of Chemical Engineers) solid flame model is proposed. Third, for estimating incident thermal radiation from fireballs one diameter away and elevations of fireballs, the Roberts point source model is recommended. Finally, for estimating incident thermal radiation from jet fires and flame length, the TNO model is suggested.
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Zhong, Yunhao, Yanhui Zhang, Chengfang Mao, and Ananchai Ukaew. "Performance, Combustion, and Emission Comparisons of a High-Speed Diesel Engine Fueled with Biodiesel with Different Ethanol Addition Ratios Based on a Combined Kinetic Mechanism." Processes 10, no. 9 (August 25, 2022): 1689. http://dx.doi.org/10.3390/pr10091689.
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In this work, different ethanol ratios (5%, 10%, 15%, and 20%) blended with biodiesel were used to investigate the effects of ethanol addition on engine performance, combustion, and emission characteristics of a high-speed diesel engine in terms of brake power, brake specific fuel consumption, brake thermal efficiency, cylinder pressure, cylinder temperature, heat release rate, NOx, CO, and soot emissions. First, a three-dimensional CFD model was established by AVL-Fire combined with the CHEMKIN code. Then, an improved kinetic mechanism with 430 reactions and 122 species was developed by combining a three-component biodiesel combustion mechanism and ethanol mechanism to accurately simulate the blended fuel combustion processes. The results indicated that compared with biodiesel, the maximum brake specific fuel consumption increased by 6.08%, and the maximum brake thermal efficiency increased by 2.09% for the blended fuel. In addition, NOx and CO emissions for EE20 were reduced by 29.32% and 39.57% at full engine load. Overall, the ethanol addition can significantly decrease pollution emissions.