Teses / dissertações: "Exhaust system"

1

Fuller, Andrew D. "A flow rate measurement system for a mobile emissions measurement system". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1903.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xv, 111 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 89-91).

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2

Sherman, Jay Michael. "Inhalation exposure system for diesel exhaust particulates". Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=2844.

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Thesis (M.S.)--West Virginia University, 2003.
Title from document title page. Document formatted into pages; contains vii, 112 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 109-112).

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3

Bernier, Bryan. "Aerodynamic Characteristics of a Gas Turbine Exhaust Diffuser with an Accompanying Exhaust Collection System". Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5126.

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The effects of an industrial gas turbine's Exhaust Collector Box (ECB) geometry on static pressure recovery and total pressure loss were investigated in this study experimentally and computationally. This study aims to further understand how exit boundary conditions affect the performance of a diffuser system as well as the accuracy of industry standard computational models. A design of experiments approach was taken using a Box-Behnken design method for investigating three geometric parameters of the ECB. In this investigation, the exhaust diffuser remained constant through each test, with only the ECB being varied. A system performance analysis was conducted for each geometry using the total pressure loss and static pressure recovery from the diffuser inlet to the ECB exit. Velocity and total pressure profiles obtained with a hotwire anemometer and Kiel probe at the exit of the diffuser and at the exit of the ECB are also presented in this study. A total of 13 different ECB geometries are investigated at a Reynolds number of 60,000. Results obtained from these experimental tests are used to investigate the accuracy of a 3-dimensional RANS with realizable k-[epsilon] turbulence model from the commercial software package Star-CCM+. The study confirms the existence of strong counter-rotating helical vortices within the ECB which significantly affect the flow within the diffuser. Evidence of a strong recirculation zone within the ECB was found to force separation within the exhaust diffuser which imposed a circumferentially asymmetric pressure field at the inlet of the diffuser. Increasing the ECB width proved to decrease the magnitude of this effect, increasing the diffuser protrusion reduced this effect to a lesser degree. The combined effect of increasing the ECB Length and Width increased the expansion area ratio, proving to increase the system pressure recovery by as much as 19% over the nominal case. Additionally, the realizable k-[epsilon] turbulence model was able to accurately rank all 13 cases in order by performance; however the predicted magnitudes of the pressure recovery and total pressure loss were poor for the cases with strong vortices. For the large volume cases with weak vortices, the CFD was able to accurately represent the total pressure loss of the system within 5%.
M.S.M.E.
Masters
Mechanical and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering; Thermofluids

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4

Fang, Xitian 1963, e Deming 1967 Wan. "Integrated automotive exhaust engineering : uncertainty management". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34631.

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Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2006.
Includes bibliographical references (p. 104-108).
The global automotive industry has entered a stagnating period. Automotive OEMs and their tier suppliers are struggling for business growth. One of the most important strategies is to improve the engineering efficiency in the product development process. The engineering uncertainties have been identified as the main obstacles in the Lean Engineering practices. This study will be focused on the engineering development process of ArvinMeritor Emission Technologies. The lean engineering principles and techniques are applied to the current product development process. The Value Stream Mapping and Analysis method is used to identify the information flow inside the current engineering process. Based on the value stream map, the uncertainties at various development stages in the process are identified. The Design Structure Matrix is used to identify any unplanned design iteration, which results in lower engineering efficiency. The House of Quality is used to prioritize the importance of the iterations. The suggested excel program can effectively evaluate the effect of task duration, probability, impact and learning curve assumption.
(cont.) In order to quantitatively predict the effects of the uncertainties, a System Dynamic model is specifically developed for the current engineering of Emission Technologies. The results clearly indicate the control factors for on-time delivery, efficient resource allocation, and cost reduction. This study has integrated the techniques from system engineering, system project management, and system dynamics. An improved automotive exhaust engineering process is proposed.
by Xitian Fang and Deming Wan.
S.M.

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5

Wijewardane, M. Anusha. "Exhaust system energy management of internal combustion engines". Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/9829.

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Today, the investigation of fuel economy improvements in internal combustion engines (ICEs) has become the most significant research interest among the automobile manufacturers and researchers. The scarcity of natural resources, progressively increasing oil prices, carbon dioxide taxation and stringent emission regulations all make fuel economy research relevant and compelling. The enhancement of engine performance solely using incylinder techniques is proving increasingly difficult and as a consequence the concept of exhaust energy recovery has emerged as an area of considerable interest. Three main energy recovery systems have been identified that are at various stages of investigation. Vapour power bottoming cycles and turbo-compounding devices have already been applied in commercially available marine engines and automobiles. Although the fuel economy benefits are substantial, system design implications have limited their adaptation due to the additional components and the complexity of the resulting system. In this context, thermo-electric (TE) generation systems, though still in their infancy for vehicle applications have been identified as attractive, promising and solid state candidates of low complexity. The performance of these devices is limited to the relative infancy of materials investigations and module architectures. There is great potential to be explored. The initial modelling work reported in this study shows that with current materials and construction technology, thermo-electric devices could be produced to displace the alternator of the light duty vehicles, providing the fuel economy benefits of 3.9%-4.7% for passenger cars and 7.4% for passenger buses. More efficient thermo-electric materials could increase the fuel economy significantly resulting in a substantially improved business case. The dynamic behaviour of the thermo-electric generator (TEG) applied in both, main exhaust gas stream and exhaust gas recirculation (EGR) path of light duty and heavy duty engines were studied through a series of experimental and modelling programs. The analyses of the thermo-electric generation systems have highlighted the need for advanced heat exchanger design as well as the improved materials to enhance the performance of these systems. These research requirements led to the need for a systems evaluation technique typified by hardware-in-the-loop (HIL) testing method to evaluate heat exchange and materials options. HIL methods have been used during this study to estimate both the output power and the exhaust back pressure created by the device. The work has established the feasibility of a new approach to heat exchange devices for thermo-electric systems. Based on design projections and the predicted performance of new materials, the potential to match the performance of established heat recovery methods has been demonstrated.

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6

Gräsberg, Pontus. "IC-Engine Source Characterisation and exhaust system simulations". Thesis, KTH, Marcus Wallenberg Laboratoriet MWL, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299411.

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To be able to predict the sound pressure level emitted by a exhaust system one must be able to describe the source. The source in the form of an engine can linearly be described as a source strength and a source impedance. An IC-engine can acoustically have a non-linear part meaning that the source characteristics have a dependency on the load. The first part of this work investigates through simulation's in GT-Power how these characteristics are affected by the load connected to the source. The Second part of the work combines the source characteristics with simulations of a muffler and compares to different methods of getting the pressure at the outlet of the exhaust. The first method is direct simulation of the muffler in COMSOL Multiphysics and the second is a transfer matrix based calculation. How sensitive the results at the outlet are to changes in the source impedance is also tested. It is concluded that using five loads for the multiload method in the form of five different lengths on the pipe connecting the engine and muffler works when the pipe have the same length as would be seen in reality. Furthermore, the pipe lengths should have a small range, 100 mm between largest and smallest pipe length giving good results. The source characteristics were at least above 1000 RPM stable enough as to not significantly change the sound pressure level at the outlet.
För att kunna modellera ljudtrycket som avges från ett avgassystem behöver man kunna beskriva källan. Källan i form av en bränslemotor kan linjärt beskrivas som en källstyrka och en källimpedans. En bränslemotor kan dock ha en akustisk ickelinjär del vilket medför att källan kan vara beroende utav vilken last i form av ljuddämpare den är kopplad till. Första delen av detta arbete undersöker genom motorsimuleringar i GT-Power hur lasten påverkar källkarakteristiken. Den andra delen av arbetet kombinerar källkarakteristiken med simuleringar av ljuddämparen och jämför olika metoder för att få ljudtrycket vid utloppet av avgassystemet. Den första metoden för detta är direkt simulering av ljuddämparen i COMSOL Multiphysics där källkarakteristiken inkluderas och den andra metoden är transfermatris baserad. Det testas också hur känsligt ljudtrycket vid utloppet av ljuddämparen är för variationer i impedansen. För källkarakteristiken används fem laster per uträkning och slutsatsen dras att lasten i form av röret mellan motor och ljuddämpare samt ljuddämparen bör vara så lik som möjligt det riktiga systemet. Utöver det dras slutsatsen att en liten variation i det kopplande rörets längd ger bättre resultat och att en variation mellan största och minsta röret på 100 mm ger bra resultat. Till sist dras slutsatsen att för varvtal över 1000 RPM är källkarakteristiken tillräckligt stabil för att ge stabila resultat vid utloppet av ljuddämparen, medans under 1000 RPM kan det vara stabilt nog men här är validering viktigare.

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7

Pech, Ondřej. "Výzkum efektivních způsobů odsávání". Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-364821.

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Many production technologies generate a variety of gas pollutants, which are unhealthy. The aim is therefore to minimize the content of such gas pollutants in the work environment. The highest capture efficiency of gas pollutants offers the local exhausting. Its disadvantage is the necessity to surround the source of pollutants, or to be as close as possible which is usually not technically or technologically possible. A possible alternative is to use a reinforced exhaust system that achieves greater capture distances. In the initial stage of the solution of the dissertation, a review of reinforced exhaust systems was carried out. Further, an existing measurement system was modified for measurements with the partition above the exhaust slot and the measurement system was partially automated. In order to investigate the case with pollutants having a lower density than the air, the workbench - the partition was moved above the exhaust slot. Based on of the literature review, a modification of the reinforced slot exhaust system was proposed. The modification consisted in the adjustment of the air inlet adjustment where a set of holes and a tube assembly were used instead of the slot. Such setup allowed for higher flow turbulence and thus for an increased exhaust efficiency. Subsequently, the inlet streams from the slot, holes and tubes were visualized by the smoke method. Further measurements were carried out by the tracer gas method for the determination of the exhaust efficiency. Measurements of velocity fields in front of the proposed configurations of the reinforced slot exhaust hood were also carried out. In conclusion, an energy performance assessment was carried out by means of the measurement of the electric power input to the fans with the determination of the electric loss power.

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8

Meyer, Eric Todd. "Evaluation of exhaust flowrate measurement techniques for a mobile emissions monitoring system". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1855.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xii, 89 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 67-68).

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9

Shade, Benjamin C. "A performance evaluation of the MEMS an on-road emissions measurement system study /". Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1592.

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Thesis (M.S.)--West Virginia University, 2000.
Title from document title page. Document formatted into pages; contains xii, 118 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 102-104).

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10

Wiemeler, Dirk. "Aero acoustic on automotive exhaust systems". Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0018.

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Dans les systèmes d'échappement automobile, les sources de bruit d'origine aéro-acoustique représentent une partie importante du contenu fréquentiel, objectivement et subjectivement identifiable. De robustes procédures de tests ont été mises en place mais la simulation du contenu du bruit n'a pas encore fait ses preuves dans les processus de développement au quotidien. Cette thèse montre que le bruit aéro-acoustique provenant de sources type dipôle est dominant pour ce qui concerne les systèmes automobiles. La simulation des écoulements à l'origine de ces bruits spécifiques combinée avec les outils de calculs acoustiques classiques est très lourde voir tout simplement impossible. Le but de cette thèse est d'analyser la loi d'échelle pour des modèles de sources compactes, permettant de déterminer l'émission de la puissance acoustique selon différentes configurations géométriques "simples" et généralement répandues (par ex. tube perforé, diaphragme placé dans un tube…) basées sur des données empiriques. Il est démontré à l'aide de simulations que son utilisation est simple et que la précision de ces modèles de sources est satisfaisante si l'on ne s'écarte pas trop des géométries déjà analysées
On automotive exhaust systems aero acoustic noise is a dominant and critical noise content, which is clearly objectively and subjectively detectable. Robust test procedures are established but the simulation of this noise content has not gained ground in the real life development processes. This thesis shows that the dominating characteristic of the aero acoustic noise of automotive systems is dipole noise. The simulation of these specific noise sources with classical computational areo acoustics is very cumbersome or even just impossible. The aim of the thesis is a review of the scaling law approach for compact source models, enabling the determination of the sound power emission of discret configurations based on empirical data. Application simulations show that the use of these source models is simple and that the accuracy is acceptable within the geometry limits analysed

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11

El, Nemr Yasser. "Acoustic modeling and testing of exhaust and intake system components". Licentiate thesis, KTH, MWL Strömningsakustik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48070.

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Intake and exhaust orifice noise contributes to interior and exterior vehicle noise. The order noise radiated from the orifice of the intake and exhaust systems is caused by the pressure pulses generated by the periodic charging and discharging process and propagates to the open ends of the duct systems. The propagation properties of these pulses are influenced by the dimensions and acoustic absorption properties of the different devices in the intake/exhaust line (muffler, turbocharger, catalyst, intercooler, particulate filter, etc.). Additional to this pulse noise, the pulsating flow in the duct system generates flow noise by vortex shedding and turbulence at geometrical discontinuities. Several turbochargers, catalytic converters, Diesel particulate filters and intercoolers elements were investigated and analyzed by performing two-port acoustic measurements with and without mean flow at both cold conditions (room temperature) and hot conditions (running engine test bed) to investigate these devices as noise reduction elements. These measurements were performed in a frequency range of 0 to 1200 Hz at no flow conditions and at flow speeds: 0.05 and 0.1 Mach. A new concept for the acoustic modeling of the catalytic converters, Diesel particulate filters and Intercoolers, and a new geometrical model for the turbocharger were developed. The whole test configuration was modeled and simulated by means of 1-D gas dynamics using the software AVL-Boost. The results were validated against measurements. The validation results comprised the acoustic transmission loss, the acoustic transfer function and the pressure drop over the studied test objects. The results illustrate the improvement of simulation quality using the new models compared to the previous AVL-Boost models.

QC 20111115

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12

Bai, Mo, e Mahabaleshwar Sagar Parampalli. "Accelerated Engine Suspension Load Prediction and Exhaust System Displacement Simulation". Thesis, KTH, Maskinkonstruktion (Inst.), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-218029.

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In today’s competitive automotive industry, most companies are trying to make their new designs and features implemented in their products to be ahead of their competitors. However, in the preliminary design stage of CEVT vehicles, dynamic simulation consumes excessive amount of time depending on the complexity of the dynamic model and simulation settings. It is beneficial and possible to shorten the simulation time. This thesis focuses on reducing the dynamic simulation time in ADAMS/Car in engine suspensions’ early development stage. Five simulation time reducing methods, i.e., reducing end time in driver control maneuver, stopping similar simulations, converting specific flexible parts to rigid parts, properly increasing the step size and performing simulation for engine suspension subsystem instead of the full vehicle system, were proposed and investigated separately to study their effects on the simulation time and the accuracy of the fatigue damage results of the engine suspension. With the proper combination of the five methods, total dynamic simulation time was effectively reduced to 61% and the variation of fatigue damage results of each engine suspension component was controlled within 30%. Dynamic modelling of an exhaust system is also included in this thesis and it provides referential data for the packaging design of exhaust system.
I dagens konkurrensutsatta bilindustri försöker de flesta företag att göra sina nya mönster och funktioner implementerbara i sina produkter för att vara före sina konkurrenter. I det preliminära konstruktionsstadiet av CEVT-fordon förbrukar dynamisk simulering dock en stor tid beroende på komplexiteten hos den dynamiska modellen och simuleringsinställningarna. Det är fördelaktigt och möjligt att förkorta simuleringstiden. Denna avhandling fokuserar på att minska den dynamiska simuleringstiden i ADAMS / Car i motorupphängningens tidiga utvecklingsstadium. Med hjälp av bakgrundsstudier och erfarenheter från CEVT’s personal provades fem olika sätt att minska simuleringstiden, samtidigt som simuleringsresultatens noggrannhet kontrollerades. Varje metod användes separat i simuleringen för att studera effekten på resultatens noggrannhet. I slutet kombineras alla metoder i simuleringen för att få bästa möjliga simuleringstid utan att förlora noggrannhet. Genom att kombinera de fem metoderna reducerades den totala dynamiska simuleringstiden till 61% och variationen i utmattningsskadans resultat av varje motorupphängningskomponent kontrollerades inom 30%. Dynamisk modellering av ett avgassystem ingår också i denna avhandling, vilket ger referensdata för framtida förpackningsdesign av avgassysteme

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13

Bush, Philip David. "Development of guidelines for exhaust system design from fundamental gas dynamics studies". Thesis, University of Strathclyde, 2000. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24271.

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This thesis details an experimental and computational investigation of the relationship between exhaust system geography, the exhaust port pressure history and the gas exchange process in reciprocating four-stroke engines. The study was conducted in four phases. In the first phase, an extensive experimental programme was undertaken, during which key engine performance indicators together with exhaust and intake system manifold pressure and temperature data were recorded on a Rover 1.4 litre 16-valve K series engine. Measured data from each test were used to validate computational predictions. In the second phase the effect of the phasing of pressure waves at the exhaust port was systematically studied using a modified version of the validated model. The relationships between key engine performance indicators and the pressure at the exhaust port during specific periods of the exhaust event were identified. In the third phase, exhaust system gas dynamics were studied and the effect of exhaust system junctions and components on the transmitted and reflected characteristics of pressure waves were investigated. A method was identified by which the dynamic pressure history at the exhaust port could be broken down into its principal incident and reflected pressure wave components.

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14

Tiwari, Aseem. "Design, development and qualification of Compact Mobile Emissions Measurement System (CMEMS) for real-time on-board emissions measurement". Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4944.

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Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains xiii, 125 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 121-125).

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15

Cartwright, Justin W. "The Characterization of an Externally Cooled Exhaust Manifold". The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1385982535.

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16

Cirillo, Emily D. "Development of a micro-dilution tunnel system for in-use, on-board heavy duty vehicle particulate matter emissions measurement". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2085.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xiii, 147 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 120-124).

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17

González, García-Cervigón Maria Inmaculada. "Adsorption and oxidation of NO to NO2 over a renewable activated carbon from coconut". Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/13678.

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The NOx health and environmental problems make necessary to reduce this gaseous emission from different sources. Furthermore, its increase in the last years and the difficulties to remove it with after-treatment systems already in the market make more urgent the development of new techniques. The purpose of this investigation is to study the low temperature catalytic oxidation of NO to NO2 and its adsorption over a renewable activated carbon (AC) from coconut shell. The present research presents the results of experimental work carried out using a laboratory scale reactor to investigate the low temperature catalytic oxidation of NO. Activated carbon was housed in the reactor and tests were carried out with different reactor sizes, different activated carbon forms and shapes, different gas mixtures at different temperatures and different levels of humidity to simulate dry and wet particulate-free diesel engine exhaust gas. The effects of addition of ozone in the gas on the NO oxidation were also explored. Gas analysis upstream and downstream of the catalytic reactor was carried out in all cases during the charge and regeneration of the AC. An extensive literature review in conjunction with measurement of some properties of the activated carbon helped to understand better its characteristics and behaviour. The results of this study indicate that in the case of dry gas, the activated carbon initially acts as an adsorber and only after operation of several hours, the NO oxidation that takes place in the reactor results in increased NO2 levels in the product gas. The NO conversion is affected by the activated carbon form and reaction conditions including temperature, humidity, oxygen, NO, CO2 content in the inlet gas, temperature, space velocity, linear gas velocity, residence time, reactor shape, AC pretreatment and lifespan. Water vapour has a detrimental effect on the conversion of NO to NO2 before the AC reaches the steady-state conditions. On the other hand, ozone is effective in converting NO to NO2 at room temperature. This research has developed some findings not studied or reported by other researches before and confirms and/or complements results reported in the literature review by other groups, which will benefit the development of a renewable after-treatment system of NOx emissions.

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Riddle, Wesley C. "Design and evaluation of the emissions measurement components for a heavy-duty diesel powered vehicle mobile emissions measurement system (MEMS)". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1939.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains viii, 167 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 128-130).

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Walder, John. "Transient Flow Simulations in Exhaust After Treatment Systems". Thesis, Linköpings universitet, Mekanisk värmeteori och strömningslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-168799.

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The exhaust after treatment system is responsible for removing particulates and contaminants from the exhaust gases. The flow entering the SCR, a catalyst utilizing ammonia to reduce NOx emissions, was studied. The quality and distribution of flow entering the SCR plays an important role in the efficiency of the systems. A CFD study was completed initially investigating the impact on solution accuracy of different modeling approaches with respect to pressure drop and flow uniformity entering SCRs. Next, multi-species simulations were completed to analyze different modeling approaches impact on ammonia distribution and flow rates through SCRs. RANS, URANS, and DES simulations were compared in both stages. An in depth analysis of the current methodology utilized at Scania to investigate pressure drop and velocity uniformity index concluded that there is minimal benefit in changing the current methodology. DDES and URANS simulations yielded results containing less than 2% difference when compared with the current methodology. Expanding the investigation to include ammonia mixing yielded interesting disparities between simulation methods with respect to multispecies flow characteristics. This difference was attributed to disparities between the initial mixing of ammonia within the domain. The RANS and URANS simulations contained a much larger dispersion of ammonia, accredited to an increased false diffusion. DDES simulations are very computationally costly but by following time reducing processes, DDES simulations could be used early in the design and analysis phase of exhaust after treatment systems to analyze ammonia distribution and mixing.

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20

Still, Michael Joseph. "All-air moisture and energy recovery system for fuel cell exhaust". Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17051.

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21

Hitchen, David John. "A microwave plasma system for the treatment of vehicle exhaust emissions". Thesis, University of Liverpool, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421033.

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22

Ravikumar, Aneesh. "Mechanical modelling of gaskets in exhaust after-treatment system of trucks". Thesis, Linköpings universitet, Mekanik och hållfasthetslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-168162.

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With the world proceeding towards a clean and sustainable environment,the creation of technology and its implementation also needs to be sustain-able. The importance of combustion engine vehicles to meet more stringentemission standards puts a requirement on the industry to develop suitableafter-treatment systems to meet those standards. It is a matter of quality,technical soundness and the brand reputation of Scania to ensure effectivetreatment of the exhaust gases before being emitted into the environment.Thus the components involved in the after-treatment system (also called si-lencer) need to be designed accordingly. The scope of this work deals withthe second stage of after-treatment systems called the Diesel Particulate Fil-ter Assembly. This assembly consists of a filter tube with a graphite gasketaround it resting against a support ring welded to the tube. The weld cre-ates a tube distortion that contributes to tolerance issues. This work dealswith developing robust and efficient simulation methodologies to predict thesealing performance of the gasket. Component tests were done to understandthe material behavior in compression, shear and tension. A friction test tostudy the tangential behavior was also performed. Using the test data, dif-ferent material models were developed to recreate the behavior of the gasket.Parameter optimization was used to optimize the material model for a hyper-elastic reduced polynomial model of degree 3 (or Yeoh model) to minimizethe error between the test curve and the predicted simulation curve.

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23

KISHORE, ARAVIND. "Numerical Modeling of Pollutant Dispersal from Watercraft Exhaust Systems". University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1212173987.

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24

Melchiorre, Simone. "Delayed Detached Eddy Simulation of the exhaust system of a LMP2 car". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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Talking about race cars' aerodynamics, effects that the exhaust system has on the latter can not be ignored. In the past years, engineers take advantage of these high-energy flows which have turned to be the key point in many car competitions. The purpose of this thesis is to identify a methodology for the fluid dynamic simulation of the exhaust gases, in cross-flow configuration, aimed to predict the effect on the car's aerodynamic load through the application of Delayed Detached Eddy Simulations (DDES). Furthermore, it wants to evaluate the differences, in terms of loads and fluid structures, between this model and the Reynolds-averaged Navier–Stokes Eddy Viscosity Model (RANS-EVM). The car considered for the study is the Dallara P217 built by Dallara to compete in the 2017 World Endurance Championship (WEC). The basic hypothesis in DDES modelling is the linearization of the vehicle-exhaust system. The flows inside the exhaust pipes (Sub-Model Simulation) and the external flows outside the car (Full-Model Simulation) were therefore independently simulated. The Full-Model simulation models the exhaust flows through the use of a velocity inlet condition; the data necessary for the definition of this boundary condition are the results coming from the Sub-Model simulation.

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Allam, Sabry. "Acoustic modelling and testing of advanced exhaust system components for automotive engines". Doctoral thesis, KTH, Aeronautical and Vehicle Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49.

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The increased use of the diesel engine in the passenger car, truck and bus market is due to high efficiency and lower fuel costs. This growing market share has brought with it several environmental issues for instance soot particle emission. Different technologies to remove the soot have been developed and are normally based on some kind of soot trap. In particular for automobiles the use of diesel particulate traps or filters (DPF:s) based on ceramic monolithic honeycombs are becoming a standard. This new exhaust system component will affect the acoustics and also work as a muffler. To properly design exhaust systems acoustic models for diesel particulate traps are needed. The first part of this thesis considers the modelling of sound transmission and attenuation for traps that consist of narrow channels separated by porous walls. This work has resulted in two new models an approximate 1-D model and a more complete model based on the governing equations for a visco-thermal fluid. Both models are expressed as acoustic 2-ports which makes them suitable for implementation in acoustic software for exhaust systems analysis. The models have been validated by experiments on clean filters at room temperature with flow and the agreement is good. In addition the developed filter models have been used to set up a model for a complete After Treatment Device (ATD) for a passenger car. The unit consisted of a chamber which contained both a diesel trap and a Catalytic Converter (CC). This complete model was also validated by experiments at room temperature. The second part of the thesis focuses on experimental techniques for plane wave decomposition in ducts with flow. Measurements in ducts with flow are difficult since flow noise (turbulence) can strongly influence the data. The difficulties are also evident from the lack of good published in-duct measurement data, e.g., muffler transmission loss data, for Mach-numbers above 0.1-0.2. The first paper in this part of the thesis investigates the effect of different microphone mountings and signal processing techniques for suppressing flow noise. The second paper investigates in particular flow noise suppression techniques in connection with the measurement of acoustic 2-ports. Finally, the third paper suggests a general wave decomposition procedure using microphone arrays and over-determination. This procedure can be used to determine the full plane wave data, e.g., the wave amplitudes and complex wave numbers k+ and k-. The new procedure has been applied to accurately measure the sound radiation from an unflanged pipe with flow. This problem is of interest for correctly determining the radiated power from an engine exhaust outlet. The measured data for the reflection coefficient and end correction have been compared with the theory of Munt [33] and the agreement is excellent. The measurements also produced data for the damping value (imaginary part of the wavenumber) which were compared to a model suggested by Howe [13]. The agreement is good for a normalized boundary layer thickness less than 30-40

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Graff, Christopher Dominic. "System modeling, analysis, and optimization methodology for diesel exhaust after-treatment technologies". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35681.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.
Includes bibliographical references (p. 152-155).
Developing new aftertreatment technologies to meet emission regulations for diesel engines is a growing problem for many automotive companies and suppliers. Balancing manufacturing cost, meeting emission performance, developing competitive engine power, reducing weight and operational costs are all tradeoffs that companies and operators have to resolve for new aftertreatment technologies. However, no single technology has been able to address the wide range of performance and cost objectives in this field. The traditional design philosophy of developing components, optimizing them for particular operation states, and then adding them together into a system may not yield the best solution to this complex problem. Manufacturers may not be able to offer the best balance of performance and cost developing systems in this manner. Two useful product development tools that can address this issue is Systems Architecture and multidisciplinary design optimization (MDO). This thesis develops and exercises a framework for modeling, designing, analyzing, and optimizing of complex diesel exhaust after-treatment systems.
(cont.) The methodology presented addresses the issue of complexity of systems and their components, and how to use systems architecture to develop a modeling technique that allows for flexibility in design, coding and analysis. The framework also addresses the analysis of exhaust system models, and utilizes multidisciplinary system design optimization to improve the design of exhaust systems. It also shows how using a system design and optimization methodology can yield better system designs than the more traditional design and development method that addresses only one technological component at a time. Two case studies are presented to validate the framework and methodology, and a set of design solutions for each case are found. A modeling and simulation tool was also developed for this thesis, and presented. The valuable information gleaned from this analysis can assist engineers and designers in identifying design directions and developing complete diesel emissions treatment solutions.
by Christopher Dominic Graff.
S.M.

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Rojas, Néstor Y. "Diesel exhaust system influences on transient particulate emissions and particle size distribution". Thesis, University of Leeds, 2001. http://etheses.whiterose.ac.uk/2292/.

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The behaviour of particulate matter emissions from a Ford XLD 4T, passengercar diesel engine through a practical exhaust system in place was investigated during transient conditions, namely cold start and fast acceleration. Particulate emissions were measured at four sampling points through the exhaust system and the changes in particulate total mass concentration, total number concentration, particle size distribution and Carbon/SOF fractions were determined for various engine operating conditions. Each cold start test consisted of a step-change cold-start with fast acceleration, reaching one of the following target operation conditions: Idle, 1500rpm - 15kW, 2250rpm - 15kW, 2250rpm-35kW and 3500rpm - 15kW. Two preconditioning procedures were designed to provide repeatable cold start tests. These consisted of a) Idle operation for 4 hours the day before the test, followed by overnight soak; and b)10 minutes at high engine speed operation. Fast acceleration tests consisted of idle preconditioning followed by a step change to the target operation conditions. The particulate matter changes through the exhaust system were shown to be dependent on the previous operational history of the engine, idle conditions being effective at forming particle deposits. The amount of particulate deposited or blown out from the exhaust system constituted a significant fraction of the total engine exhaust emissions in a significant number of cold start and acceleration tests. The changes in particle concentration did not occur throughout the system in the same fashion. The catalyst produced predominantly particle number and mass reduction and the second silencer was a more efficient particle collector than the first silencer. From the first silencer, particles were resuspended more easily and in many more cases. Regarding the chemical composition, high-load conditions produced lower Solvent Organic Fraction (SOF) than their low load counterpart. However, the SOF did not change significantly through the exhaust system. Part of this work consisted of examining the use of the Electrical Low Pressure Impactor (ELP1) to estimate particulate mass emissions. It was observed that the ELP1 tended to overestimate the number of particles in the large (>0.1 (im) size range. This greatly affected the conversion from total particle number concentration to particle mass concentration. A correction based on comparison between the electrical and gravimetric methods (ELPI vs. Andersen Impactors) in the common size range for both techniques was proposed. Transient and steady-state tailpipe emission factors, expressed as grams of particulate per unit of engine work in kWh, were calculated from the test results and used to estimate the effect of transients on total cycle emissions in cycles with a different design from those followed in this work. The ELPI proved to be useful, yet limited for particle collection on Transmission Electron Microscope (TEM) grids in several size ranges. TEM images of particles were analysed and their fractal dimension determined.

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Skousen, Aaron Bradley. "Design, Fabrication and Testing of a Pressurized Oxy-Coal Reactor Exhaust System". BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7518.

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One of the challenges facing engineers is to provide clean, sustainable, affordable and reliable electricity. One of the major pollutants associated with coal combustion is CO2. A proposed technology for efficiently capturing CO2 while producing electricity is pressurized oxy-combustion (POC). The first objective of this work is to design, build and demonstrate an exhaust system for a 20 atmosphere oxy-coal combustor. The second objective of this work is to design and build mounts for a two-color laser extinction method in the POC. The POC reactor enables the development of three key technologies: a coal dry-feed system, a high pressure burner, and an ash management system. This work focuses on cooling the flue gas by means of a spray quench and heat exchanger; controlling the reactor pressure and removing ash from the flue gas. Designs and models of each component in the exhaust systems are presented. Methods to test and assemble each system are also discussed. The spray quench flow rate was measured as a function of pump pressure. Theoretical models for the required amount of water in the spray quench, the flue gas composition, the length and number of tubes in the heat exchanger, and the cyclone collection efficiency are presented. The combined exhaust system is assembled and ready to be tested once issues involving the control system and burner are resolved.

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Soares, António César Galvão. "Fatigue life assessment of exhaust systems for naval gas turbines". Master's thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/6919.

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Puttagunta, Rupesh Kumar. "Characterization and kinetic evaluation of UV system used to treat commercial kitchen exhaust emissions a thesis presented to the faculty of the Graduate School, Tennessee Technological University /". Click to access online, 2008. http://proquest.umi.com/pqdweb?index=0&did=1605147091&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1269016483&clientId=28564.

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Themi, Vasos. "Multi-Physics Co-Simulation of Engine Combustion and Exhaust Aftertreatment system: Development of a Multi-Physics Co-Simulation Framework of Engine Combustion and Exhaust Aftertreatment for Model-Based System Optimisation". Thesis, University of Bradford, 2017. http://hdl.handle.net/10454/17403.

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The incorporation of detailed chemistry models in internal combustion engine simulations is becoming mandatory as new combustion strategies and lower global emissions limits are setting the path towards a more efficient engine cycle simulation tool. In this report, the computational capability of the stochastic-based Kinetics SRM engine suite by CMCL Innovations is evaluated in depth. With the main objectives of this research to create a multi-physics co-simulation framework and improve the traditional engine modelling approach of individual simulation of engine system parts, the Kinetics SRM code was coupled with a GT-SUITE engine model to fill in the gap of accurate emissions predictions from one-dimensional simulation tools. The system was validated against testing points collected from the AJ133 V8 5L GDI engine running on the NEDC. The Kinetics SRM model is further advanced through a sensitivity analysis for the “unknown” internal parameters of the chemistry tool. A set of new parameters’ values has been established that gives the best overall trade-off between prediction accuracy and computational time. However, it still showed high percentage errors in modelling the emissions and it was discovered that the specific software package currently cannot simulate directed injection events. This is the first time a Kinetics SRM/GT-SUITE coupled code is employed to model a full 8-cylinder GDI SI engine. The approach showed some limitations regarding the Kinetics SRM and that in many cases is limited to trend analysis. The coupled engine – combustion emissions model is then linked with an exhaust aftertreatment system model in MATLAB Simulink, creating a multi-physics model-based co-simulation framework of engine performance, combustion characterisation, in-cylinder emissions formation and aftertreatment efficiency.

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Lee, Yeaw-Lip. "Particle-sizing system fro scanning electron microscope images of solid-propellant combustion exhaust". Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/28440.

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Ramanathan, Sathish Kumar. "Linear Acoustic Modelling and Testing of Exhaust Mufflers". Thesis, KTH, Aeronautical and Vehicle Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4340.

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Intake and Exhaust system noise makes a huge contribution to the interior and exterior noise of automobiles. There are a number of linear acoustic tools developed by institutions and industries to predict the acoustic properties of intake and exhaust systems. The present project discusses and validates, through measurements, the proper modelling of these systems using BOOST-SID and discusses the ideas to properly convert a geometrical model of an exhaust muffler to an acoustic model. The various elements and their properties are also discussed.

When it comes to Acoustic properties there are several parameters that describe the performance of a muffler, the Transmission Loss (TL) can be useful to check the validity of a mathematical model but when we want to predict the actual acoustic behavior of a component after it is installed in a system and subjected to operating conditions then we have to determine other properties like Attenuation, Insertion loss etc,.

Zero flow and Mean flow (M=0.12) measurements of these properties were carried out for mufflers ranging from simple expansion chambers to complex geometry using two approaches 1) Two Load technique 2) Two Source location technique. For both these cases, the measured transmission losses were compared to those obtained from BOOST-SID models.

The measured acoustic properties compared well with the simulated model for almost all the cases.

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Korremla, Shiva K. Sainoju. "Experimental investigation of steady state heat transfer phenomenon in Pontiac G6 vehicle exhaust system". To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2007. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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Krueger, Warren Allyn. "Plasma and neutral gas jet interactions in the exhaust of a magnetic confinement system". Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/13665.

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Chhabra, Manish. "Source Characterization using an Experimental Method and Prediction of Insertion of the Exhaust System". University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin154399673454236.

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Rankin, Bret A. "Design and development of a microwave enhanced diesel soot oxidation system". Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=1058.

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Thesis (M.S.)--West Virginia University, 1999.
Title from document title page. Document formatted into pages; contains xiv, 347 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 272-276).

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Cliff, Rachel. "Peripheral blood markers of central nervous system effects following controlled human exposure to diesel exhaust". Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57879.

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Epidemiological and animal studies suggest that exposure to airborne pollutants may negatively impact the central nervous system (CNS). It is thought that traffic related air pollution (TRAP), and other forms of combustion-derived pollutants, may induce a maladaptive activation of the CNS immune system, however, the exact pathway is not understood. Animal models and epidemiological studies have inherent limitations including potential interspecies differences and residual confounding. Given this, the aim of this research is to examine effects of TRAP on the CNS using a controlled human exposure. 27 healthy adults were exposed to two conditions: filtered air (FA) and diesel exhaust (DE) (300µg PM₂.₅/m³) for 120 minutes, in a double-blinded crossover study with exposures separated by four-weeks. Prior to and at 0, 3, and 24 hours following exposure, serum and plasma were collected and analyzed for inflammatory cytokines IL-6 and TNF-α, the astrocytic protein S100b, the neuronal cytoplasmic enzyme neuron specific enolase (NSE), and brain derived neurotrophic factor (BDNF). The hypothesis was that IL-6, TNF-α, S100b and NSE would increase and BDNF would decrease following DE exposure. Changes in levels of biomarkers were assessed using a paired t-test to compare the change from baseline at each post-exposure timepoint following DE or FA exposure. A linear mixed effects model was build including exposure and timepoint as covariates, and subject ID as a random effect. Age and gender were examined as potential effect-modifying variables. At no time-point following exposure to DE was a significant increase from baseline seen for IL-6, TNF-α, S100b or NSE, or decrease for BDNF, relative to FA exposure. The linear mixed effects model revealed indication of diurnal behavior for S100B, NSE and BDNF; however, no significant exposure-time-point interaction, suggesting the biomarkers were not affected by DE exposure. These results indicate that short-term exposure to DE amongst young, healthy adults does not acutely affect levels of the measured biomarkers. This study does not disprove a relationship between air pollution and adverse CNS effects and suggests a need to examine the effects of TRAP on the brain using in chronic exposure models or more sensitive CNS endpoints.
Medicine, Faculty of
Population and Public Health (SPPH), School of
Graduate

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Ismail, Basel Ismail A. "The heat transfer and the soot deposition characteristics in diesel engine exhaust gas recirculation system cooling devices /". *McMaster only, 2004.

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Ames, Robin W. "Analysis of a 2007 EPA compliant diesel particulate matter sampling system". Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5245.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains xv, 133 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 91-95).

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Carlsson, Carin. "Modeling and Experimental Validation of a Rankine Cycle Based Exhaust WHR System for Heavy Duty Applications". Thesis, Linköpings universitet, Fordonssystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-81737.

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To increase the efficiency of the engine is one of the biggest challenges for heavy vehicles. One possible method is the Rankine based Waste Heat Recovery. Crucial for Rankine based Waste Heat Recovery is to model the temperature and the state of the working fluid. If the state of the working fluid is not determined, not only the efficiency of the system could be decreased, the components of thesystem might be damaged.A Simulink model based on the physical components in a system developed by Scania is proposed. The model for the complete system is validated against a reference model developed by Scania, and the component models are further validated against measurement data. The purpose of the model is to enable model based control, which is not possible with the reference model. The main focus on the thesis is to model the evaporation and condensation to determine state and temperature of the working fluid. The developed model is compared to a reference model with little differences for while stationary operating for both the components and the complete system. The developed model also follows the behavior from measurement data. The thesis shows that two phase modeling in Simulink is possible with models based on the physical components.

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Besch, Marc Cyrill. "In-line, Real-time Particulate Matter Sensors for OBD and Exhaust After-treatment System Control Applications". Thesis, West Virginia University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10110090.

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The ability to quantify particle mass and number concentrations in the exhaust stream of combustion engines during in-use operation is of critical importance for continuously monitoring and diagnosing the particulate matter removal efficiency of modern exhaust gas after-treatment systems. Extensive literature survey suggested a sensor operating on the diffusion-charging principle being optimally suited for particle measurements due to their proportional response towards particle surface area. This study was designed to determine and assess the possibility of quantifying particle emissions during on-road measurements using a prototype diffusion-charging type sensor. Such a sensor would not only allow for continuous monitoring capabilities of the exhaust particulate filters integrity, but moreover provide for a simplified tool to assess real-world particle number emissions to verify in-use emissions compliance of engines.

Evaluation of the sensor followed a three tier process, starting with fundamental sensor response analysis using a particle generator in order to develop and parameterize the underlying physical phenomena of the measurement principle. Next, examine the sensor in engine dynamometer experiments under controlled environment, and sampling from test vehicles during chassis dynamometer testing aimed at real-world like test conditions. Finally, the sensor was installed on vehicles while operated on the road over diverse driving conditions. This allowed for comparison to laboratory-grade measurement systems and the standard regulatory gravimetric particulate matter measurement method. The diffusion-charging type sensor employed in this study was observed to exhibit a response proportional to particle size D_p^1.09 and a measurement variability below 2% over consecutive tests. The sensor’s sensitivity allowed for distinguishing between Diesel particulate filter efficiencies due to soot cake layer build-up on the substrate walls. In summary, the study concluded that the diffusion-charging type sensor provided a viable method to quantify in-use particle number emissions.

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Dudar, Stephen W. "Preliminary design study of an enhanced mixing eductor system for the LHA (R) gas turbine exhaust". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FDudar.pdf.

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Lotun, Devprakash. "Design and evaluation through simulation and experimental apparatus of a small scale waste heat recovery system". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52179.

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Thesis (MScEng)--Stellenbosch University, 2001.
ENGLISH ABSTRACT: Realisation of the depletable nature of fossil fuel has increased the need for its optimal use. Increasing global pressure to reduce the emission of greenhouse gases and other harmful gases that affect the chemical cycles or destroy the greenhouse gases in the tropospheric ozone, has attracted a increased worldwide concern. Waste heat recovery devices have been around for more than 50 years and researches and scientists have been very much involved in identifying the correct type of systems to meet the requireme?ts of industries and mankind more efficiently. Waste heat can be identified in the form of unburned but combustible fuel, sensible heat discharges in drain water, and latent and sensible heat discharge in exhaust gases. In this project the feasibility of a small scale waste heat recovery system has been investigated. Sets of preliminary investigations were performed to evaluate the amount of waste heat that can be extracted from the exhaust gases of typical diesel powered truck engines. A waste heat recovery unit was designed, implemented and evaluated through simulation and experimental investigations. Preliminary calculations were performed usmg the readings presented by Koorts (1998) for a typical 6-litre diesel engine. The calculations showed that it is possible to extract about 77kW of waste heat from the exhaust gases from such an engine. A simple Rankine cycle was then investigated to be operated on the waste heat recovered. The optimal parameters for such a Rankine cycle was determined using a spreadsheet program and was found to be an optimal pressure of 800kPa with a temperature of 227.2°C and a water mass flow rate of 0.0015kgls as the working fluid. For such a Rankine cycle, based on the efficiencies of commercially available pumps, turbines and heat exchangers it was found that it is possible to extract 2782kW of power per unit mass flow rate of water. The next stage of the project was designing and implementing an exhaust gas pipe network from the engine test cells at the Centre for Automotive Engineering (CAE) located on the ground floor to the Energy Systems Laboratory (ESL) at the first floor. This pipe network was equipped with a valve system that can be operated from the ESL and allows the selection of the route of the exhaust gases and two bellows to compensate for thermal expansion. A continuous combustion unit was also linked to the exhaust gas supply pipes as an alternative source of exhaust gases. The waste heat exchanger designed and selected was purchased and linked into the exhaust gas stream after calibration tests were carried out on the same in the wind tunnel. The water supply and a steam separator were then connected to the waste heat exchanger. In the final experimental stage of the project, two sets of tests were carried out. The first set of tests was performed using exhaust gases from the continuous combustion unit and the second using exhaust gases from the internal combustion engines in CAE. Superheated steam was obtained in both cases indicating the possibility of operating a turbine with the dry steam generated. With exhaust gases originating from the continuous combustion unit, an air fuel ratio of9.14:1 was used and exhaust gases at a temperature of 540°C were obtained with an air inflow of 1400kglh and a fuel consumption rate of7.11 kg/h. The exhaust gases degraded to 360°C at the waste heat recovery inlet due to losses through the bare pipes. 11.12kW of energy was extracted from the exhaust gases to the water stream with an efficiency of 98%. With the exhaust gases from the 10-litre diesel internal combustion engine, an exhaust gas flow rate of O.22kgls was used and with a heat transfer efficiency of 89%, 18.5kW of power was extracted at the waste heat recovery unit. This represents a 4.9% of the thermal content of the fuel used. A rate of energy production balance on the internal combustion engine showed that 34% is lost in exhaust gases and 29% in coolant and other losses while only 37% is used produced as shaft power. The results obtained therefore show that there is ample room for further investigation for the use afwaste heat in exhaust gases of typical diesel engines. It can therefore be concluded that the aims of the project that were to set up a testing facility and an exhaust gas pipe network and evaluation of a small scale waste heat recovery apparatus were achieved. The tests performed can still be optimised with more waste heat removal from the exhaust gases of typical diesel truck engines and hence better recovery of waste heat and a reduction of fuel consumption.
AFRIKAANSE OPSOMMING: Met die besef van die kwynende beskikbaarheid van fosielbrandstof het die behoefte vir die optimale benutting van die brandstof toegeneem. Toenemende globale druk om die emissies van groenhuis gasse en ander gevaarlike gasse wat chemiese siklusse beïnvloed in die troposfeer te verrniner, geniet wêreldwye aandag. Oorskotenergie-toestelle is alreeds beskikbaar die afgelope 50 jaar en navorsers en wetenskaplikes was tot op hede betrokke met die identifisering van die korrekte tipe sisteme om meer effektief aan die industrie en samelewing se behoeftes te voldoen. Oorskotenergie bestaan uit onder andere onverbrande maar brandbare brandstof, voelbare warmte in dreinwater, en latente en voelbare warmte in uitlaatgasse. In hierdie projek word die lewensvatbaarheid van 'n kleinskaal oorskotenergie herwinningsisteem ondersoek. Voorlopige ondersoeke was gedoen om die hoeveelheid oorskotenergie te bepaal wat herwin kan word uit die uitlaatgasse van 'n tipiese 6 liter vragmotor dieselenjin. 'n oorskotenergie herwinningseenheid was ontwerp, geïmplimenteer en ge-evalueer deur similasies en eksperimentele ondersoeke. Voorlopige berekeninge was uitgevoer op data wat deur Koorts (1998) saamgestel is vir 'n tipiese vragmotor dieselenjin. Die berekeninge toon dat dit moontlik is om ongeveer 77kW oorskotenergie van die uitlaatgasse van so enjin te onttrek. Die moontlikheid was toe ondersoek om die herwinne energie te gebruik om 'n eenvoudige Rankine siklus aan te dryf. Die optimale parameters vir die Rankine siklus was bereken deur van 'n sigblad program gebruik te maak en dit was gevind dat die optimale druk is 800kPa, die optimale temperatuur is 227.2°C teen 'n water massa vloeitempo van 0.0015kg/s. Vir so 'n Rankine siklus, gebaseer op die effektiwiteit van kommersiële beskikbare pompe, turbines en warmteruilers, was dit gevind dat dit moontlik is om 2782kW drywing per eenheidsmassa vloeitempo van water, te onttrek. Die volgende stadium van die projek was die ontwerp en implimentering van 'n uitlaatgas pypnetwerk vanaf die toetsselle van die Centre for Automotive Engineering (CAE) op die grondvloer na die Energy Systems Laboratory (ESL) op die eerste vloer. Die pypnetwerk was toegerus gewees met 'n kleptstelsel wat vanaf ESL bedryf kan word en wat dit moontlik maak om die roete van die uitlaatgasse te beheer. Twee samedrukbare koppelstukke was ook ingesluit in die lang reguit pypseksie om vir termiese uitsetting te kompenseer. 'n Aaneenlopende verbrandingseenheid was ook gekoppel met die uitlaatgasse toevoerpype as 'n alternatiewe bron van uitlaatgasse. Die oorskotenergie warmteruiier wat ontwerp en geselekteer was, was aangekoop en opgekoppel met die uitlaatgas-stroom nadat kalibrasie toetse op die warmteruiier gedoen was in 'n windtonnel. Die watertoevoer en 'n stoomskeier was gekoppel aan die oorskotenergie warmteruiler. Twee toetse was uitgevoer in die finale eksperimentele stadium van die projek. Die eerste stel toetse was uitgevoer deur gebruik te maak van die uitlaatgasse van die aaneenlopende verbrandingseenheid en met die tweede toets is van die uitlaatgasse van die interne verbrandingsenjins van CAE gebruik gemaak. Oorverhitte stoom was verkry in beide gevalle en wys dus dat daar 'n moontlikheid is om 'n turbine met droë stoom aan te dryf. 'n Lug tot brandstof verhouding van 9.14 : 1 was gebruik gewees in die aaneenlopende verbrandingseenheid om uitlaatgasse te verskaf teen 540°C. Die massavloeitempo van die lug was 1400kg/h en die brandstof 7.11kg/h. Die uitlaatgasse se temperatuur het afgeneem tot 360°C tot voor die oorskotenergie herwinningseenheid as gevolg van hitteverliese vanaf die ongeïsoleerde pypnetwerk. 11.12kW energy was onttrek vanaf die uitlaatgasse en oorgedra aan die waterstroom met 'n effektiwiteit van 98%. Die 10 liter diesel interne verbrandingsenjin het uitlaatgas gelewer met 'n massa vloeitempo van O.22kg/s. 18.5kW energie was herwin gewees met 'n effektiwiteit van 89%. Dit verteenwoording 4.9% van die termiese inhoud van die brandstof gebruik. 'n Energie balans op die interne verbrandingsenjin het getoon dat 34% energie gaan verlore in die uitlaatgasse, 29% word aan die verkoelingsmiddeloorgedra en 37% is bruikbare meganiese drywing. Die resultate wat verkry is, wys daarop dat daar nog groot ruimte is vir verdere ondersoeke in die gebruik van oorskotenergie in uitlaatgasse van tipiese vragmotor dieselenjins. Die gevolgtrekking kan dus gemaak word dat die doelwitte van die projek naamlik die opstel van 'n toetsfasiliteit, installering van 'n uitlaatgasse pypnetwerk en die toets van a kleinskaalse oorskotenergie herwinningseenheid, bereik was. Die toetse wat uitgevoer was kan nog ge-optimeer word om meer energie te herwin vanaf die uitlaatgasse van 'n tipiese vragmotor dieselenjin om sodoende beter brandstofverbruik te bewerkstellig.

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Ford, Eric J. (Eric John). "The effects of lubrication system parameters and exhaust aqueous injection on diesel engine oil consumption and emissions". Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36066.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1995, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1995.
Includes bibliographical references (p. 79-81).
by Eric J. Ford.
M.S.

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Lee, Tian-Hua, e 李天華. "Active Noise Control of Engine Exhaust System". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/32327888365133352413.

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碩士
大葉大學
車輛工程研究所
90
This thesis describes two active noise control (ANC) systems for reducing undesired noise in engine exhaust systems. The first proposed controller is based on the adaptive filter using filtered-x least mean square (FXLMS) algorithm, while the other is a fixed controller of gain-scheduled active control technique for broadband attenuation with thermal effects. Both of the control algorithms are implemented on a digital signal processor (DSP) using finite impulse response (FIR) filter. In this ANC control structure, acoustic feedback is decreased by using directional microphones and backward control loudspeaker in hardware design, and considering compensation of feedback neutralization filter in control algorithm. Experiments are carried out to evaluate the attenuation performance of two proposed active control systems for synthetic random noise source, centrifugal fan noise and engine exhaust noise, respectively. The results of experiments indicate that the adaptive filter and gain-scheduled ANC controller are effective in suppressing the exhaust end noise of proposed system. The experimental comparison and analysis of proposed ANC controllers are also described in this thesis.

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Lin, Yu-Feng, e 林裕豐. "Exhaust System Design Improvement of Internal Combustion Engine". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/g496q9.

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碩士
國立臺北科技大學
車輛工程系所
98
This paper is focus on exhaust system performance improvement. To design a new exhaust system which has to keep several design limitation. 1st one is set catalyst position closer to cylinder head. 2nd is satisfy engine room space limitation. 3rd is satisfy catalyst flow uniformity index equal to 0.85 or more. 4th is keeping engine performance compares with base engine. This paper includes 2 steps, one is 3d model design step and the other is simulation step. 3D design step: Following the exhaust system layout limitation, choosing 4-2-1#1 exhaust concept to design new exhaust system. For new concept exhaust system has been created which has new catalyst position 44.9mm closer to the cylinder head than base engine. And following new flow distribution concept to change exhaust flow angle between end of manifold and catalyst front end to increase distribution area of flow into catalyst. Simulation step: - Computational Fluid Dynamics: Each cylinder was simulated in steady state condition to calculate flow uniformity (γ) on section of catalyst. Result of flow uniformity will be a index of catalyst utilization. For the final result of uniformity shows that new concept exhaust system is better the traditional one and satisfies 0.85 requirement。 - Performance simulation: Performance of engine simulation model which using new exhaust system has max. power (75.98ps@6000rpm) and max. torque (104.08N.m@4500rpm). To compare with performance of base engine simulation model and real engine test. It shows that difference of overall performance is in 1.5% which satisfies performance requirement. Follow each result of 2 steps above; the new concept exhaust manifold can keep performance in position of catalyst 44.9mm closer to cylinder head condition, and satisfies uniformity index which should improve exhaust system performance of base engine.

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Wu, GinHwa, e 吳俊樺. "Simulation of Pipeline Exhaust Process in Teppanyaki System". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/05842713597460288206.

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碩士
國立高雄應用科技大學
機械與精密工程研究所
96
Fluid flow in the pipeline will be hampered by resistance. The resistance of fluid can be divided into primary resistance and secondary resistance. Primary resistance was due to fluid friction with pipeline. Secondary resistance was happened with fluid encountering turning point and the cross-section changed. In the past, artificer usually designed pipelines by his experience in traditional industries in Taiwan. He used feelings to handle the shape of pipeline. The situation of fluid in pipeline can not be completely known. In this paper, the CFD was be used to simulate the flow in pipeline and improve its efficiency. The results of simulation show that changes in the geometry of the pipeline will lead to additional energy loss. Especially in the irregular shape of the components will result in the swirl. Different shapes of the entrance will not export the same velocity. The flow of segregation and collusion will make fluid mutual exclusion to influence the flow. To increase cross-sectional area can get better efficient than change the shape of hood. The smooth of flow may not be directly proportional to exhaust velocity. The minimum diameter department is mostly influence the efficiency of pipeline. Using the free space within plant to improve the efficiency of exhaust pipes is the best way.

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Wang, Teng Wei, e 王騰緯. "The computer-aided design of local exhaust system". Thesis, 1994. http://ndltd.ncl.edu.tw/handle/08770936145016308212.

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張峻瑋. "The Analysis and Simulation of Mufflers in Exhaust System". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/vy52n2.

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碩士
國立臺北科技大學
機電整合研究所
101
The main objective of this work is to investigate the emissions of gas flowing through the engine exhausting system, the noise and the impulse noise caused by the muffler, and the flow simulation from the transmission losses. It is also important to explore the muffler with porous media using different porosities and the interaction between muffler noises. The CFD tool has been used here to simulate the exhausting system and the flow field of the muffler. This is a three-dimensional incompressible steady-state flow which is solved by the Navier-Stokes equations. This turbulent flow is described as the RANS state of turbulence model. The Standard k-ε model is applied to solve this turbulent flow. The aerodynamically caused noise model used here are: FW-H model and the BNS model which separately show the flow field and the sound pressure distribution of the flow in unsteady state and steady state. First, the computer-aided design drawing software has been used to draw the internal flow of the muffler, constructing the grid, setting equivalent boundary conditions and appropriate numerical methods, and finally the numerical results will be obtained to compare the results with other studies. The result will be finally exported as post-processing image to do the related research.

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