Journal articles: 'Thermal computation of boiler'

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Chengguo, Fu, Feng Yipeng, Tian Yishui, Liang Mingchao, and Zhang Zhengchuan. "Design of a 1 t/h Biomass Chain Boiler and ιts Fuel Adaptability Analysis." Journal of Engineering Science and Technology Review 13, no. 5 (2020): 132–42. http://dx.doi.org/10.25103/jestr.135.17.

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The arch is an important component of a biomass boiler. Initial arch design of most boilers is generally gained through manual computation, thus resulting in uncertain reasonability of flue gas flow. Moreover, biomass fuels in the market have instable characteristics, which influence the utilization of biomass energies considerably. To address the problems concerning reasonable flue gas flow caused by the collaborative design of arch and air staging and the combustion adaptability of fuels, a cold modeling experiment of a 1 t/h biomass boiler under different staged air distribution ratios when the rear arch coverage varies was conducted using Fluent software in this study after thermal performance computation and initial structural design of grate and furnace. Furthermore, a boiler performance test based on main fuels and a combustion adaptation test of auxiliary fuels were also performed. The experiments show that the best flue gas flow in the furnace is achieved when the rear arch coverage is 60% and the primary–secondary air distribution ratio is 4:6. The mean boiler efficiency and the mean boiler heat output are 81.26% and 715.76 kW/h by using Pinus koraiensis pellets, wood–straw mixed pellets, and cotton straw briquettes as main fuels; and the tested pollutant emissions are in compliance with the limits of the national standard. The results of the combustion adaptation test reveal that the excessive particle size, the high ash content and the relatively low calorific value of biomass molded fuels are all against the combustion of biomass boilers. Fuel upgrading based on washing process and other methods is suggested. This study can provide references to the performance optimization of traditional small-scale biomass chain heating boilers.

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He, Yang, and Su Fen Li. "Research on the On-Line Model for Energy Efficiency Diagnosis of Thermal Power Pulverized Coal Boiler." Advanced Materials Research 320 (August 2011): 542–47. http://dx.doi.org/10.4028/www.scientific.net/amr.320.542.

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This paper presents one on-line model for energy efficiency calculation and analysis. The computation model of combustion rate and other related physical and chemical equations were introduced to the heat balance computing model of boiler. It established one on-line model of thermal process, which can provide the functional relationship completely in real-time measurable variables to the calculation of energy efficiency. And on that basis, the theory on deviation analysis was introduced to establish the model for energy efficiency quantitative analysis to calculate the single-factor distributed consuming difference. The situation of the CG-220/9.81-M boiler’s energy efficiency was calculated and analyzed with the diagnosis model. The calculation errors of thermodynamic parameters related and the errors between the lumped energy efficiency deviation and the sum of single-factor distributed efficiency deviation were both small. The model is reasonably accurate. The on-line model for energy efficiency diagnosis of thermal power pulverized coal boiler was established.

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Gómez, Miguel, Rubén Martín, Joaquín Collazo, and Jacobo Porteiro. "CFD Steady Model Applied to a Biomass Boiler Operating in Air Enrichment Conditions." Energies 11, no. 10 (September 21, 2018): 2513. http://dx.doi.org/10.3390/en11102513.

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A numerical model is proposed to perform CFD simulations of biomass boilers working in different operating conditions and analyse the results with low computational effort. The model is based on steady fluxes that represent the biomass thermal conversion stages through the conservation of mass, energy, and chemical species in the packed bed region. The conversion reactions are combined with heat and mass transfer submodels that release the combustion products to the gas flow. The gas flow is calculated through classical finite volume techniques to model the transport and reaction phenomena. The overall process is calculated in a steady state with a fast, efficient, and reasonably accurate method, which allows the results to converge without long computation times. The modelling is applied to the simulation of a 30 kW domestic boiler, and the results are compared with experimental tests with reasonably good results for such a simple model. The model is also applied to study the effect of air enrichment in boiler performance and gas emissions. The boiler operation is simulated using different oxygen concentrations that range from 21% to 90% in the feeding air, and parameters such as the heat transferred, fume temperatures, and emissions of CO, CO2, and NOx are analysed. The results show that with a moderated air enrichment of 40% oxygen, the energy performance can be increased by 8%, CO emissions are noticeably reduced, and NOx remains practically stable.

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Ibraheem, Amjd, and Ferenc Szodrai. "Numerical Model Analysis of Natural Gas Combustion Burners." International Journal of Engineering and Management Sciences 4, no. 1 (March 3, 2019): 67–71. http://dx.doi.org/10.21791/ijems.2019.1.9.

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Traditional power plants still the dominating power source for all the major industries and powerdemanding facilities, the most crucial facility for the whole plant operations is the industrial boiler which generatessteam, heating energy or electrical power. Boilers generate energy by combustion. The improvement of combustion efficiency could greatly influence the energy consumption and will make the boiler more efficient and cleaner (less emissions), that’s why it is important to understand the combustion and thermal flow behaviours inside the boiler. Beside experimental testing, computational work nowadays becoming more and more important due to lower cost and acceptable accuracy with minimum error. With numerical calculations method, the computational model created by a Computational Fluid Dynamics (CFD) software could reduce a lot of trial and error on experimental work. In this paper utilizing the ANSYS FLUENT 19.1 software to make crate the combustion model. The ratio of air to fuel mixture, the equivalency factor, mass flow rate of the mixture, velocity, mass fractions of the mixture components (fuel and air) and their temperatures will serve as the input parameter while the exhaust gase component mass fraction, temperature, mass flow and velocity will be monitored.

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Naď, Martin, Zdeněk Jegla, Tomáš Létal, Pavel Lošák, and Jiří Buzík. "Thermal load non-uniformity estimation for superheater tube bundle damage evaluation." MATEC Web of Conferences 157 (2018): 02033. http://dx.doi.org/10.1051/matecconf/201815702033.

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Industrial boiler damage is a common phenomenon encountered in boiler operation which usually lasts several decades. Since boiler shutdown may be required because of localized failures, it is crucial to predict the most vulnerable parts. If damage occurs, it is necessary to perform root cause analysis and devise corrective measures (repairs, design modifications, etc.). Boiler tube bundles, such as those in superheaters, preheaters and reheaters, are the most exposed and often the most damaged boiler parts. Both short-term and long-term overheating are common causes of tube failures. In these cases, the design temperatures are exceeded, which often results in decrease of remaining creep life. Advanced models for damage evaluation require temperature history, which is available only in rare cases when it has been measured and recorded for the whole service life. However, in most cases it is necessary to estimate the temperature history from available operation history data (inlet and outlet pressures and temperatures etc.). The task may be very challenging because of the combination of complex flow behaviour in the flue gas domain and heat transfer phenomena. This paper focuses on estimating thermal load non-uniformity on superheater tubes via Computational Fluid Dynamics (CFD) simulation of flue gas flow including heat transfer within the domain consisting of a furnace and a part of the first stage of the boiler.

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Yang, Dong, Long Wang, Yanshuang Bi, Beibei Xie, Gang Wang, and Danhua Yao. "ICOPE-15-C004 Thermal-hydraulic analysis and metal temperature computation for the water wall of a 1000MW ultra supercritical tower boiler with double reheat." Proceedings of the International Conference on Power Engineering (ICOPE) 2015.12 (2015): _ICOPE—15——_ICOPE—15—. http://dx.doi.org/10.1299/jsmeicope.2015.12._icope-15-_121.

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Polesek-Karczewska, Sylwia, Izabela Wardach-Święcicka, Dariusz Kardaś, and Tomasz Turzyński. "Application of a Lumped Multi-Section Model for Analyzing the Thermal Performance of a Small-Scale Biomass Boiler." Journal of Thermal Science 30, no. 3 (March 13, 2021): 1034–45. http://dx.doi.org/10.1007/s11630-021-1385-8.

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AbstractThe stationary lumped-cell model was developed and used to simulate the thermal characteristics of domestic biomass boiler with helically coiled tube heat exchanger (HCHE). The device serves as the heat source for ORC (Organic Rankine Cycle) unit and utilizes the thermal oil as the medium transferring the heat to the unit. Most of studies available in the literature refer to the CFD simulations for water flow in tube coils or in one- or two-turn coil elements. These investigations are basically focused on the determination of Nusselt number. The proposed herein model aims at determining the thermal performance of flue gas-oil HCHE while providing low CPU time. To demonstrate the model possibilities, it was used to predict the flue gas temperatures at the inlet and outlet from the heat exchange zone, based on measurement data regarding the outlet temperature of thermal oil. Six test series were considered. The computation results appeared to be in satisfactory agreement with experimental results (the discrepancies do not exceed 12%). The investigations showed that the used approach may be recommended as an alternative method that allows for fast prediction of thermal parameters for units of complex geometries, in particular the multi-coil heat exchangers.

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Kravets, Taras, Yevhen Miroshnychenko, and Andrii Kapustianskyi. "Enhancement of Technical and Economic Indicators of Power-Generating Units of Thermal Power Plants by Eliminating Flue Gas Recirculation." Energy Engineering and Control Systems 7, no. 1 (2021): 26–31. http://dx.doi.org/10.23939/jeecs2021.01.026.

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Boiler units at Ukrainian thermal power plants need to be modernized or replaced in the short run, as this is important for the national energy security. The authors determined one of possible ways to improve the efficiency indicators of coal-fired boiler units and power generating units as a whole up to the values exceeding the design ones. This variant of improvement consists in abandoning the technology of using flue gas as drying agent in pulverized coal systems and replacing it with direct discharge of the gas flow into the boiler furnace. Numerous computations were carried out to study the change of efficiency indicators and manoeuvrability of power generating units due to the replacement of the ball mill pulverizing system using flue gases for coal drying with the scheme including ball-and-race mills that use hot air as drying agent.

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Trávníček, Petr, Radovan Kukla, Tomáš Vítěz, and Jan Mareček. "Experimental determination of temperatures of the inner wall of a boiler combustion chamber for the purpose of verification of a CFD model." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 59, no. 1 (2011): 235–42. http://dx.doi.org/10.11118/actaun201159010235.

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The paper focuses on the non-destructive method of determination of temperatures in the boiler combustion chamber. This method proves to be significant mainly as regards CFD (Computational Fluid Dynamics) simulations of combustion processes, in case of which it is subsequently advisable to verify the data calculated using CFD software application with the actually measured data. Verification of the method was based on usage of reference combustion equipment (130 kW) which performs combustion of a mixture of waste sawdust and shavings originating in the course of production of wooden furniture. Measuring of temperatures inside the combustion chamber is – considering mainly the high temperature values – highly demanding and requires a special type of temperature sensors. Furthermore, as regards standard operation, it is not possible to install such sensors without performing structural alterations of the boiler. Therefore, for the purpose of determination of these temperatures a special experimental device was constructed while exploiting a thermal imaging system used for monitoring of the surface temperature of outer wall of the reference boiler. Temperatures on the wall of the boiler combustion chamber were determined on the basis of data measured using the experimental device as well as data from the thermal imaging system. These values might serve for verification of the respective CFD model of combustion equipment.

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Fueyo, N., V. Gambo´n, C. Dopazo, and J. F. Gonza´lez. "Computational Evaluation of Low NOx Operating Conditions in Arch-Fired Boilers." Journal of Engineering for Gas Turbines and Power 121, no. 4 (October 1, 1999): 735–40. http://dx.doi.org/10.1115/1.2818534.

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In the present paper, a computational model is used to simulate the aero-dynamic, thermal, and chemical conditions inside an arch-fired coal boiler. The model is based on the Eulerian-Eulerian concept, in which Eulerian conservation equations are solved both for the gas and the particulate phases. A NOx formation and destruction submodel is used to calculate the local concentration of NO. The model is used to simulate a range of operating conditions in an actual, 350 MW, arch-fired boiler, with the aim of reducing, using primary measures, the emissions of NOx. The model results shed some light on the relevant NOx-formation mechanisms under the several operating conditions. Furthermore, they correlate well quantitatively with the available field measurements at the plant, and reproduce satisfactorily the tendencies observed under the different operating modes.

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Taler, Jan, Bohdan Weglowski, and Marcin Pilarczyk. "Monitoring of thermal stresses in pressure components using inverse heat conduction methods." International Journal of Numerical Methods for Heat & Fluid Flow 27, no. 3 (March 6, 2017): 740–56. http://dx.doi.org/10.1108/hff-03-2016-0091.

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Purpose The purpose of this paper is to present a method for monitoring transient thermal stresses. This paper also presents the analysis of thermal stresses of boiler pressure element heating during the start-up in real conditions. The inverse methods are used to determine the wall temperature, whereas the commercial software ANSYS is used to determine the thermal stresses in the pressure component. Design/methodology/approach The method is based on the solution of the inverse heat conduction problem. Thermal stresses are determined indirectly taking into account the measured temperature values at selected points on the outer wall of a pressure component. First, the transient temperature distribution in the entire pressure element is calculated, and then, thermal stresses are determined by the finite element method. Measured pressure changes are used to determine the stresses resultant from the internal pressure. Findings The obtained stresses and temperature in the thick-walled pipe are illustrated and compared with experimental data. Satisfactory agreement was found between computational and experimental results. Originality/value The method can be used in the monitoring of thermal and mechanical stresses during the boiler’s start-up and shut-down. Because the temperature distribution at each time level is determined, it can be applied as a thermal load during the structural analysis.

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Rodrigues, C. P., M. A. Lansarin, A. R. Secchi, and T. F. Mendes. "SIMULATION OF PULVERIZED COAL FIRED BOILER: REACTION CHAMBER." Revista de Engenharia Térmica 4, no. 1 (June 30, 2005): 61. http://dx.doi.org/10.5380/reterm.v4i1.3551.

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This work is part of a joint project to built a computational tool for power plant simulation, dealing specifically with the reaction chamber (place of the boiler where the fuel is burned). In order to describe the conversion of chemical energy to thermal energy, an onedimensional pseudo-homogeneous mathematical model, with variable physical properties, and based on mass and energy balances, was developed. The equations were implemented in the gPROMS simulator and the model parameters were estimated using the module gEST of this software, with experimental data from a large-scale coal-fired utility boiler and kinetic data from the open literature. The results showed that the model predicts the composition of the outlet combustion gas satisfactorily.

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Boiko, E. A., and I. V. Zagorodnii. "Integrated research of slaging intensityof the boilerunit heating surfaceswhen burning non-project fuels." Power engineering: research, equipment, technology 22, no. 6 (March 26, 2021): 101–16. http://dx.doi.org/10.30724/1998-9903-2020-22-6-101-116.

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THE PURPOSE. Comprehensive research of the slagging intensity is the heating surfaces of the BKZ-420-140 boiler unit with solid slag removal at the Abakan CHP when burning non-project fuels. The relevance of the work is due to the technical necessity and economic feasibility of conversion boiler units to combustion of non-design coals. METHODS. The problem has been analyzed by methodology for conducting complex tests, measurements and processing of experimental data, as well as the results of experimental and computational studies of a boiler unit when operating on coals of various qualities. RESULTS. Qualitative and quantitative parameters for assessing the properties of off-design coals and their behavior in real operating conditions of radiation, semi-radiation and convective conditions, taking into account their modes and design functions, have been obtained. CONCLUSION: A computational analysis of the operating modes of boiler units when burning non-design fuels showed that a promising technology for involving non-design coals in the fuel and energy balance of a thermal power plant is providing a scientifically based mixture of design and nondesign fuels.Analysis of the slagging and polluting properties of non-design coals makes it possible to predict changes in the characteristics of the thermal efficiency of heating surfaces and to develop many practical recommendations for optimizing the parameters of the cleaning equipment installed on the boiler.Also, mixtures of fuels were determined for which the wall temperatures of the metal of the outlet stack of the superheater increase, which significantly reduces the strength characteristics of the surface.The assessment and prediction of the reliability of the heating surface is carried out by calculating the temperature of the metal wall in the most heat-stressed place.

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Crnomarkovic, Nenad, Miroslav Sijercic, Srdjan Belosevic, Dragan Tucakovic, and Titoslav Zivanovic. "Influence of application of Hottel’s zonal model and six-flux model of thermal radiation on numerical simulations results of pulverized coal fired furnace." Thermal Science 16, no. 1 (2012): 271–82. http://dx.doi.org/10.2298/tsci110627126c.

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Difference of results of numerical simulation of pulverized coal fired furnace when mathematical models contain various radiation models has been described in paper. Two sets of numerical simulations of pulverized coal fired furnace of 210 MWe power boiler have been performed. One numerical simulation has contained Hottel?s zonal model, whereas the other numerical simulation has contained six-flux model. Other details of numerical simulations have been identical. The influence of radiation models has been examined through comparison of selected variables (gas-phase temperature, oxygen concentration, and absorbed radiative heat rate of surface zones of rear and right furnace walls), selected global parameters of furnace operation (total absorbed heat rate by all furnace walls and furnace exit gas-phase temperature). Computation time has been compared as well. Spatially distributed variables have been compared through maximal local differences and mean differences. Maximal local difference of gas-phase temperature has been 8.44%. Maximal local difference of absorbed radiative heat rate of the surface zones has been almost 80.0%. Difference of global parameters of furnace operation has been expressed in percents of value obtained by mathematical model containing Hottel?s zonal model and has not been bigger than 7.0%. Computation time for calculation of 1000 iterations has been approximately the same. Comparison with other radiation models is necessary for assessment of differences.

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Zima, Wieslaw. "Analysis of temperature drops on the wall thickness of a supercritical boiler water-wall tube." Thermal Science 23, Suppl. 4 (2019): 1091–100. http://dx.doi.org/10.2298/tsci19s4091z.

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The paper presents selected results of numerical computations related to simulations of a supercritical power boiler evaporator operation. A detailed analysis is carried out of temperature drops on the thickness of the water-wall tube and the tube fin. A comparison is also made between the results obtained at the fin division into one and two control volumes. The tube cross-sections analysed along the tube length and including the fins are divided into 24 control volumes, for which 2-D transient heat conduction equations are formulated. The 1-D equations describing the principles of mass, momentum, and energy conservation are solved on the side of the working fluid. A convective condition, described by an empirical heat transfer coefficient, is set on the water-wall tube inner surface. The developed mathematical model is a distributed parameter model. The numerical computations are performed for a boiler operating in a power plant in Poland. The analysis takes account of the non-uniformity of the furnace chamber thermal load along its height.

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Askarova, Aliya, Pavel Šafařík, Aizhan Nugymanova, Saltanat Bolegenova, Valeriy Maximov, and Symbat Bolegenova. "MINIMIZATION OF TOXIC EMISSIONS DURING BURNING LOW-GRADE FUEL AT KAZAKHSTAN THERMAL POWER PLANT." Acta Polytechnica 60, no. 3 (July 1, 2020): 206–13. http://dx.doi.org/10.14311/ap.2020.60.0206.

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This paper presents new results of computational experiments on the implementation of Overfire Air (OFA) technologies using an example of a combustion chamber of the BKZ-75 boiler of the Shakhtinskaya power plant (Shakhtinsk, Kazakhstan) burning high-ash Karaganda coal. The effect of mass air flow through special nozzles located above the burner level on the flow aerodynamics, temperature fields, concentration fields of carbon monoxide CO and nitrogen NO over the entire volume of the combustion chamber was studied. The studied characteristics were compared for various percentages of supplying additional air through OFA injectors: OFA is 0% (basic version), 10% and 18 %. It was shown that the installation of OFA injectors leads to a change in the field of the total velocity vector, temperature, and concentrations of carbon oxides and nitrogen. An increase in the percentage of air supplied through OFA injectors to 18% leads to a decrease in the concentrations of carbon monoxide CO by about 36% and nitrogen oxide NO by 25% compared with the base case. The obtained results will optimize the process of burning pulverized fuel in the combustion chamber of the BKZ-75 boiler, increase the efficiency of fuel burnout, reduce harmful emissions and introduce OFAtechnology at other coal-burning thermal power plants.

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Lee, Sang Yeol, Kwang Cheol Oh, Chung Ceon Lee, Yun Seong Choi, Jae Heun Oh, and DaeHyun Kim. "Thermal Efficiency Characteristics According to Structure Change of Wood Pellet Boiler Using Computational Fluid Dynamics." New & Renewable Energy 12, no. 3 (September 25, 2016): 59–67. http://dx.doi.org/10.7849/ksnre.2016.9.12.3.59.

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Zeng, De Liang, Zhao Liang Guan, Can Peng, and Man Zhang. "Real-Time Pollution Monitoring Model of Convection Heating Surfaces Based on Coal Online Soft Sensing." Advanced Materials Research 622-623 (December 2012): 1421–24. http://dx.doi.org/10.4028/www.scientific.net/amr.622-623.1421.

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This paper presents a real-time pollution monitoring model of convection heating surfaces based on coal online soft sensing, This model reality the optimization calculation of clean factor and get the information of coal moisture, ash content and ultimate only according to the existing measuring points and data in the Distributed Control System (DCS) of thermal power plants, no need to use additional equipment. Used this technique in 1000MW power units and the result shows that, the computational accuracy of clean factor has greatly improved, which will correct the boiler blowing operation.

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Euh, Seung Hee, Sagar Kafle, Yun Sung Choi, Jae-Heun Oh, and Dae Hyun Kim. "A study on the effect of tar fouled on thermal efficiency of a wood pellet boiler: A performance analysis and simulation using Computation Fluid Dynamics." Energy 103 (May 2016): 305–12. http://dx.doi.org/10.1016/j.energy.2016.02.132.

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Filkoski, Risto, Ilija Petrovski, and Piotr Karas. "Optimization of pulverised coal combustion by means of CFD/CTA modeling." Thermal Science 10, no. 3 (2006): 161–79. http://dx.doi.org/10.2298/tsci0603161f.

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The objective of the work presented in this paper was to apply a method for handling two-phase reacting flow for prediction of pulverized coal combustion in large-scale boiler furnace and to assess the ability of the model to predict existing power plant data. The paper presents the principal steps and results of the numerical modeling of power boiler furnace with tangential disposition of the burners. The computational fluid dynamics/computational thermal analysis (CFD/CTA) approach is utilized for creation of a three-dimensional model of the boiler furnace, including the platen superheater in the upper part of the furnace. Standard k-e model is employed for description of the turbulent flow. Coal combustion is modeled by the mixture fraction/probability density function approach for the reaction chemistry, with equilibrium assumption applied for description of the system chemistry. Radiation heat transfer is computed by means of the simplified P-N model, based on the expansion of the radiation intensity into an orthogonal series of spherical harmonics. Some distinctive results regarding the examined boiler performance in capacity range between 65 and 95% are presented graphically. Comparing the simulation predictions and available site measurements concerning temperature, heat flux and combustion efficiency, a conclusion can be drawn that the model produces realistic insight into the furnace processes. Qualitative agreement indicates reasonability of the calculations and validates the employed sub-models. After the validation and verification of the model it was used to check the combustion efficiency as a function of coal dust sieve characteristics, as well as the impact of burners modification with introduction of over fire air ports to the appearance of incomplete combustion, including CO concentration, as well as to the NOx concentration. The described case and other experiences with CFD/CTA stress the advantages of numerical modeling and simulation over a purely field data study, such as the ability to quickly analyze a variety of design options without modifying the object and the availability of significantly more data to interpret the results. .

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Pfeiffelmann, Björn, Michael Diederich, Fethi Gül, Ali Cemal Benim, Andreas Hamberger, and Markus Heese. "Analysis of combustion, heat and fluid flow in a biomass furnace." E3S Web of Conferences 128 (2019): 03003. http://dx.doi.org/10.1051/e3sconf/201912803003.

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A waste wood burning boiler with 200kW thermal power is investigated by experiments and numerically. Temperature measurements are performed in the furnace and in the heat exchanger sectionsin the downstream. Exit exhaust gas composition is also measured. Flow, heat transfer and combustion in the furnace, and forced convection on the water side are numerically analyzed. The water side calculations are used to obtain boundary conditions for the furnace by heat transfer coefficients. For validating the adopted mathematical/numerical formulation, the predictions are compared with measurements.A satisfactory agreement between the predictions and measurements is observed, confirming the validity of the applied computational procedures.

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Drobenko, B. D. "Computational experiment for determination of the cyclic durability of a boiler drum of a thermal power plant." Materials Science 48, no. 1 (July 2012): 76–82. http://dx.doi.org/10.1007/s11003-012-9474-1.

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Abdollahi, Navid, and Ramin Haghighi-Khoshkhoo. "Thermodynamic and Numerical Analysis of Tangentially Fired Boiler for Increasing Efficiency and Reducing Environmental Pollution." Periodica Polytechnica Mechanical Engineering 62, no. 1 (November 23, 2017): 65. http://dx.doi.org/10.3311/ppme.11416.

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The evaluation of heat transfer and fluid mechanics mechanisms to increase the thermal efficiency and combustion quality in heavy industries, such as power plants, are important and significant issues in the field of engineering sciences, which can lead to significant advances. In this regard, the present paper has been developed with thermodynamic and numerical simulations of the MONTAZER GHAEM Power Plant boiler to study the increase in efficiency and reduce environmental pollution. Also in this research, the results of practical tests have been used to verify the simulations. The thermodynamic simulation results show that the required fuel consumption of the burners in current operating conditions is not 9.1 kg/s, but it is 8.1 kg/s. The low efficiency of the set, which leads to the injection of more than the required amount of fuel to the boiler, cause the non-corresponding power generation for injected fuel, which results in the reduction of the plant thermal efficiency from 36.4% to 33.9%. The results of computational fluid dynamics show that the lightness of natural gas combustion products and, the no-flow accumulation in the lower parts of the furnace, reduce the produced steam, which results in power loss at the exit. Numerical results also show that the highest rate of NOX production occurs near the burners due to the high flame temperature and high oxygen mass fraction and consequently, the non-uniform distribution of heat in the furnace.

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Zhou, Guo Qiang, Li Yang, Shi Gui Lv, and Li Li Liu. "An Inverse Heat Transfer Problem about Crack of Boiler Furnace Wall Based on Infrared Thermographic Temperature Measurement." Advanced Materials Research 815 (October 2013): 813–20. http://dx.doi.org/10.4028/www.scientific.net/amr.815.813.

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A three-dimensional physical and mathematical models of the heat transfer in the furnace specimen with an internal defect were established. Combined with the theory of infrared thermographic temperature measurement, using the L-M method, the inverse heat transfer problem of the boiler furnace wall bricks with crack was investigated. The size of defect was accurately estimated. Conclusions can be drawn by computational analysis, firebrick played a major role in the furnace thermal insulation effect. When firebrick fails, the inspection surface temperature is abnormal, and the temperature difference between the outer surface of the defect and that of the normal wall is an exponential relationship with the increase of defect depth.

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Ozdemir, Mustafa Bahadir, and Mustafa Emre Ergun. "Experimental and numerical investigations of thermal performance of Al2O3/water nanofluid for a combi boiler with double heat exchangers." International Journal of Numerical Methods for Heat & Fluid Flow 29, no. 4 (April 1, 2019): 1300–1321. http://dx.doi.org/10.1108/hff-05-2018-0189.

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PurposeThis study aims to focus on usage of Al2O3/water nanofluid as working fluid in a combi boiler. The plate heat exchanger located at the bottom of the combi boiler has been used for heating the domestic water in the present study. Al2O3/water nanofluid has also been used in obtaining of the heat energy provided from combustion. Therefore, thermal performance of Al2O3/water has been determined by comparing water and nanofluid-water mixture. The present study also investigates heat transfer rates as numerical and experimental for varying cold side outlet temperatures, comparatively.Design/methodology/approachThe present study has included both experimental and numerical methodologies. The experimental setup consists of main heat exchanger, atmospheric burner, circulation pump and plate-type heat exchanger in which the Al2O3/water nanofluid was used as working fluid to heat the domestic water. In the numerical part of the study, a commercial computational fluid dynamic code has been used to model heat rate and thermal efficiency of the heat exchanger used.FindingsIt has been concluded that the predicted results are in satisfactorily good agreement with the measured data. In the experimental part of the study, the flow rate of Al2O3/water nanofluid was kept constant during the experiments. The flow rates of the water by which the heated Al2O3/water nanofluid mixture was cooled via the plate heat exchanger have been changed as 3, 4, 5 and 6 lpm. The domestic water temperatures that were kept constant have also been changed as 40°C, 45°C, 50°C, 55°C and 60°C. It has been concluded that the Al2O3/water nanofluid thermal efficiency has been 16 per cent better than pure water.Originality/valueThe main originality of the present study is that thermal efficiency of the plate-type heat exchanger when Al2O3/water mixture nanofluids are used as there are limited studies related to the usage of Al2O3/water mixture nanofluids in the plate-type heat exchanger not only experimental but also numerical methodologies.

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Antonescu, Nicolae, and Paul-Dan Stanescu. "Mathematical Determination of Thermal Load for Fluidised Bed Furnaces Using Sawdust." Mathematical Modelling in Civil Engineering 10, no. 2 (June 1, 2014): 1–10. http://dx.doi.org/10.2478/mmce-2014-0006.

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Abstract For technical applications, a physical model capable of predicting the particle evolution in the burning process along its trajectory through the furnace is very useful. There are two major demands: all the thermo-dynamic processes that describe the particle burning process must be accounted and the model must be written in such equation terms to allow the intervention for parameter settings and particle definition. The computations were performed for the following parameters: furnace average temperature between 700 and 1200 °C, size of the sawdust particle from 4 to 6 mm and fix carbon ignition between 500 and 900 °C. The values obtained for the characteristic parameters of the burning process ranged from 30 to 60 [kg/(h·m3)] for the gravimetrical burning speed WGh and from 150 to 280 [kW/m3] for the volumetric thermal load of the furnace QV. The main conclusion was that the calculus results are in good agreement with the experimental data from the pilot installations and the real-case measurements in the sawdust working boiler furnaces or pre-burning chambers. Another very important conclusion is that the process speed variation, when the furnace temperature changes, confirms the thermo-kinetic predictions, namely that the burning process speed decreases when the furnace temperature increases.

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Gil, Juan D., Jerónimo Ramos-Teodoro, José A. Romero-Ramos, Rodrigo Escobar, José M. Cardemil, Cynthia Giagnocavo, and Manuel Pérez. "Demand-Side Optimal Sizing of a Solar Energy–Biomass Hybrid System for Isolated Greenhouse Environments: Methodology and Application Example." Energies 14, no. 13 (June 22, 2021): 3724. http://dx.doi.org/10.3390/en14133724.

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The water–energy–food nexus has captured the attention of many researchers and policy makers for the potential synergies between those sectors, including the development of self-sustainable solutions for agriculture systems. This paper poses a novel design approach aimed at balancing the trade-off between the computational burden and accuracy of the results. The method is based on the combination of static energy hub models of the system components and rule-based control to simulate the operational costs over a one-year period as well as a global optimization algorithm that provides, from those results, a design that maximizes the solar energy contribution. The presented real-world case study is based on an isolated greenhouse, whose water needs are met due to a desalination facility, both acting as heat consumers, as well as a solar thermal field and a biomass boiler that cover the demand. Considering the Almerian climate and 1 ha of tomato crops with two growing seasons, the optimal design parameters were determined to be (with a solar fraction of 16% and a biomass fraction of 84%): 266 m2 for the incident area of the solar field, 425 kWh for the thermal storage system, and 4234 kW for the biomass-generated power. The Levelized Cost of Heat (LCOH) values obtained for the solar field and biomass boiler were 0.035 and 0.078 €/kWh, respectively, and the discounted payback period also confirmed the profitability of the plant for fuel prices over 0.05 €/kWh. Thus, the proposed algorithm is useful as an innovative decision-making tool for farmers, for whom the burden of transitioning to sustainable farming systems might increase in the near future.

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Grądziel, Sławomir, and Karol Majewski. "Simulation of heat transfer in combustion chamber waterwall tubes of supercritical steam boilers." Chemical and Process Engineering 37, no. 2 (June 1, 2016): 199–213. http://dx.doi.org/10.1515/cpe-2016-0017.

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Abstract The paper presents the results of numerical computations performed for the furnace chamber waterwalls of a supercritical boiler with a steam output of 2400 × 103 kg/h. A model of distributed parameters is proposed for the waterwall operation simulation. It is based on the solution of equations describing the mass, momentum and energy conservation laws. The aim of the calculations was to determine the distribution of enthalpy, mass flow and fluid pressure in tubes. The balance equations can be brought to a form where on the left-hand side space derivatives, and on the right-hand side – time derivatives are obtained. The time derivatives on the right-hand side were replaced with backward difference quotients. This system of ordinary differential equations was solved using the Runge-Kutta method. The calculation also takes account of the variable thermal load of the chamber along its height. This thermal load distribution is known from the calculations of the heat exchange in the combustion chamber. The calculations were carried out with the zone method.

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Habib, M. A., H. E. Emara-Shabaik, and I. Al-Zaharnah. "NUMERICAL INVESTIGATION OF THERMAL AND PHYSICAL CHARACTERISTICS OF CIRCULATING FLOW IN BOILER RISERS USING A NONLINEAR DYNAMIC MODEL." Computational Thermal Sciences 2, no. 1 (2010): 1–17. http://dx.doi.org/10.1615/computthermalscien.v2.i1.10.

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Mamudu, Angela O., Ebenezer Okonkwo, Stephen I. Okocha, Emeka E. Okoro, Francis Elehinafe, and Kevin Igwilo. "The Design of an Integrated Crude Oil Distillation Column with Submerged Combustion Technology." Open Chemical Engineering Journal 13, no. 1 (February 28, 2019): 7–22. http://dx.doi.org/10.2174/1874123101912010007.

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Objective: Generally, Petroleum refineries are put in place to convert or refine unprocessed crude oil into more useful products using both physical separation and chemical conversion processes. Albeit, different refining unit are subsets of the physical separation category. The atmospheric and vacuum distillation unit seems to be more prominent. Conventionally, the crude atmospheric residue cannot be further heated in an atmospheric condition due to: coke formation, pipes plugging, thermal cracking and straining of the furnace. A vacuum distillation column is therefore required. Methods: This study, therefore, focuses on the limitations, “over straining of the furnace to provide the necessary heat” and “non-reliance on the additional re-boiler since it only acts as a heat exchanger”. An integrated distillation column with a capacity of 10,000 barrel per day was therefore designed for the concurrent production of all distillate cuts. Results: This was achieved through the introduction of a submerged combustion zone at the stripping section of the column where Naphtha was utilized as the source of fuel. Verification of this approach was also conducted using Autodesk invention software and a finite element analysis tool to evaluate both thermal and computational fluid analysis impact. Overall, all derived distilled products met the American Society for Testing and Material Standard Table 6.

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Chernikov, V. A., E. L. Kitanin, E. Yu Semakina, and E. E. Kitanina. "Theoretical study of the application of the outlet diffuser of a gas turbine as a steam circuit superheater of a combined gas-steam plant." Vestnik IGEU, no. 5 (December 30, 2020): 26–37. http://dx.doi.org/10.17588/2072-2672.2020.5.026-037.

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Currently, thermal insulation of GTU output diffusers uses insulation of their inner surface. This is an expensive and complicated technological procedure. For gas turbines as part of CCGT, in order to reduce the cost of insulation and at the same time increase the useful power of the turbine, cooling the diffuser outer surface with a steam stream of a steam circuit can be an alternative way of internal insulation. Steam and gas parameters of a combined cycle plant with a CCGT-450T, as well as the results of experimental and computational studies of the GTU SGT5-3000E gas turbine exhaust channel model were used. The calculations of the efficiency of the surface cooling of the diffuser with the steam coming from the steam circuit were carried out using the analytical method. A scheme of a superheater located on the outer surface of the GTU outlet diffuser operating in a combined cycle is proposed. Analytic evaluation of its effectiveness showed that the surface area of the GTU diffuser of the type SGT5-3000E is sufficient to provide the necessary overheating of low-pressure steam. Installation of such a heat exchanger using the outer surface of the diffuser provides a decrease of the temperature of its outer wall from 537 to 200 оC. The study validity is confirmed by a patent for an invention. It has been established that the use of the outer surface of the GTU outlet diffuser instead of the heat exchange surface of the low pressure superheater of the utilizer boiler can be applied at CCGT unit to reduce heat and hydraulic losses in the diffuser path and in the utilizer boiler path.

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Du, Yongbo, Chang’an Wang, Pengqian Wang, Yi Meng, Zhichao Wang, Wei Yao, and Defu Che. "Computational fluid dynamics investigation on the effect of co-firing semi-coke and bituminous coal in a 300 MW tangentially fired boiler." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 233, no. 2 (June 22, 2018): 221–31. http://dx.doi.org/10.1177/0957650918783923.

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In this paper, the effect of co-firing semi-coke in a 300 MW tangentially fired boiler was numerically investigated. The results indicate that the incomplete combustion heat loss and NO x emission both increase with semi-coke co-fired ratio. Semi-coke may be injected into the furnace at a different height, which can lead to different thermal efficiency and NO x emission. It is suggested that semi-coke should not be fed from the top or bottom layer burners, since this could give rise to high carbon content respectively in fly ash and bottom slag. In addition, injecting semi-coke from the top burners could significantly increase the NO x emission. Under 1/2 co-firing ratio, the optimal fuel allocation is that feeding semi-coke from the B, D, and E layer burners. The growth in semi-coke particle size could increase the unburned carbon loss and NO x emission. It is highly recommended to reduce the unburned carbon loss under semi-coke co-fired condition by increasing the stoichiometric ratio of primary air for semi-coke. As it is increased from 0.25 to 0.3, the combustion efficiency of the co-fired condition is 99.47%, the same as when only firing bituminous coal, and the NO x emission is about 30% higher.

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Prokopov, M., S. Sharapov, Yu Merzlyakov, and D. Gusev. "The energy efficiency concept and implementation prospects of the jet thermocompression principle in small heat energy." Energy and automation, no. 2(54) (June 22, 2021): 39–51. http://dx.doi.org/10.31548/energiya2021.02.039.

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The expediency of the implementation of the principle of steam thermal compression to improve the energy efficiency of sources of electricity and heat supply of small heat power engineering is substantiated. The results of thermodynamic analysis and numerical optimization of the parameters of the compressor steam-turbine cycle of a small cogeneration power plant are presented. A jet step-down thermotransformer has been tested - as an alternative to traditional boiler heating. On the basis of the conducted thermodynamic analysis, a new combined cycle of a step-down thermotransformer has been developed, which ensures efficient conversion of the supplied energy (mainly in the form of fuel heat) into the heat carrier flow of the heat supply system with the required temperature level 50 ... 90 °C). The fundamental difference between the considered thermal transformer and steam compressor heat pumps is the replacement of a mechanical compressor with a steam thermocompressor module (STC-unit). The working process in the STK-module is realized by using the liquid phase of the refrigerant, which boils up during expiration, subcooled to saturation, as an active medium of a jet compressor. Injection of steam from the evaporator is provided due to the fine-dispersed vapor-droplet structure formed in the outlet section of the active flow nozzle. A program for the numerical study of the working process of a step-down thermal transformer was prepared and tested, on the basis of which multivariate calculations were carried out. On the basis of computational studies, the area of achievable indicators of the proposed heat supply system has been established; the area of initial operating parameters corresponding to the maximum values of the conversion coefficient and exergy efficiency was determined; comparative indicators of the main parameters of the investigated thermal transformer on various working substances in the range of operating modes as a heat pump or a refrigerating machine were obtained. Key words: workflow, steam thermocompressor, step-down thermotransformer, energy efficiency, heat pump mode

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Li, Xiao Ming, and Ai Jie Wang. "Economic Analysis and Comparison of Heat Pump Systems Using Wastewater with Traditional Air Condition." Advanced Materials Research 113-116 (June 2010): 10–13. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.10.

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The paper presents the economic comparing of heat pump using wastewater with other heating and cooling technology for buildings. The coal burning boiler, oil fired boiler, gas burning boiler and electric boiler were chosen to compare with heat pump using wastewater. A profitability evaluation of the investment in above-mentioned four projects and heat pump was carried out, using dynamic annual computation cost. In the research, the periods of time in which the investment is going to return itself were established. The results indicate that initial investment and dynamic annual computation cost of heat pump are lowest except to coal burning boiler. Therefore in current energy and environment policy, heat pump using wastewater as source is worth of popularizing.

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Zhao, Hai Qian, and Zhong Hua Wang. "Study on Novel Thermal Insulation Structure of Thermal Recovery Boiler." Advanced Materials Research 512-515 (May 2012): 1311–14. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.1311.

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Based on the existing problem of thermal insulation structure of thermal recovery boiler , a novel thermal insulation structure of thermal recovery boiler is designed. The novel thermal insulation structure was used on a boiler in field test, and its thermal insulation characteristics were tested. According to the test data, thermal conductivities of the novel and the conventional thermal insulation structure were calculated. Contrast analyses indicated that thermal insulation characteristic of the novel thermal insulation structure for thermal recovery boiler was better than that of the conventional thermal insulation structure.

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Anead, Hosham S., Khalid F. Sultan, and Ayat Ahmed. "Utilizing the Computation Intelligence Technique for Boiler Pressure Controlling." IOP Conference Series: Materials Science and Engineering 765 (March 17, 2020): 012051. http://dx.doi.org/10.1088/1757-899x/765/1/012051.

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Minchev, N. V. "Methodological Support for Applying the Method of Majority Reservation in Measuring Channels." Journal of the Russian Universities. Radioelectronics 24, no. 1 (February 26, 2021): 59–68. http://dx.doi.org/10.32603/1993-8985-2021-24-1-59-68.

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Introduction. For hazardous industries, the reliability of information and measuring equipment must ensure an almost complete absence of failure events, with their probability as low as 10-6. This requirement can be satisfied using various approaches, one of which is reservation. Reservation methods are classified into several types depending on such factors, as the operating mode of an object, failure types, frequency rate, etc. Majority redundancy schemes are rarely used in measuring equipment, particularly in measuring channels, largely because this method was initially aimed at improving the reliability of discrete digital devices. Thus far, no mathematical support for applying the method of majority reservation in measuring channels of analogue values has been developed. This gap determined the relevance of this study.Aim. To develop a methodological support for applying the method of majority reservation with the purpose of improving the level of measurement accuracy.Materials and methods. Both Russian and foreign sources published over the past 40 years on the topic of processing small samples when designing measuring channels for information and measuring systems were reviewed. The nonparametric Mann-Whitney rank test was applied to process small samples. Other research methods included mathematical modelling, as well as the mathematical apparatus of measurement theory andтsystems theory.Results. A measuring module with a redundant structure was simulated. Parametric and nonparametric rank criteria were considered. An algorithm allowing identification of the failure of a channel in a measuring module with a redundant structure was developed. The computational complexity of the developed algorithm is estimated by a polynomial of the second degree.Conclusion. The use of nonparametric rank criteria for processing small samples, as well as diagnostic situations for various combinations of these criteria, supports statistically grounded decision on the state of measuring channels. In the future, this method will be applied for diagnostic control of the serviceability of technological equipment used in fuel combustion, namely in boiler plants and installations for thermal waste destruction.

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Janic, Todor, Sasa Igic, Nebojsa Dedovic, Darijan Pavlovic, Jan Turan, and Aleksandar Sedlar. "Thermal power of small scale manually fed boiler." Thermal Science 19, no. 1 (2015): 329–40. http://dx.doi.org/10.2298/tsci130104046j.

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This study reviews test results of the combustion of square soybean straw bales used as fuel in manually fed boiler with nominal thermal power of 120 kWth. The influence of the mass flow rate (180, 265, 350, 435, and 520 kg h-1) of inlet air and flue gas recirculation (0%, 16.5%, and 33%) fed to the boiler furnace was continuously monitored. Direct method was used for determination of the boiler thermal power. Correlation between boiler thermal power and bale residence time has been observed and simple empirical equation has been derived. General conclusions are as follows: the increase of the flow rate of inlet air passing through the boiler furnace results in decrease of the bale residence time and increase of the boiler thermal power. Share of the flue gas recirculation of 16.5% increases bale residence time and decreases average boiler thermal power in all regimes except in the regime with inlet air flow rate of 265 kg h-1. In regime with 0% flue gas recirculation boiler thermal power was higher than nominal in regimes with 435 and 520 kg h-1 inlet air flow rates. In regimes having inlet air mass flow rate of 350 kg h-1 boiler thermal power is equal to the nominal power of 120 kWth.

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Zeng, Yu, and Fuchao Cheng. "Automatic control system of boiler thermal energy in thermal power plant based on artificial intelligence technology." Thermal Science 25, no. 4 Part B (2021): 3141–48. http://dx.doi.org/10.2298/tsci2104141z.

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Thermal processes tend to have large inertia and hysteresis, non-linearity, and slow time-varying. Therefore, the fixed-parameter proportional integral derivative conventional regulation system cannot meet the higher and higher control requirements in production. Based on this research background, the paper proposes an automatic control method for thermal boiler steam based on artificial intelligence technology. Through the real-time monitoring of the boiler, the state monitoring method is used to estimate the influence factors of the boiler, and the estimated error output is artificially supplemented to realize the accurate control of the boiler. After being put on the market, it is found that the control method proposed in the article can overcome the randomness and inertia of the temperature and accurately realize the temperature control of the boiler. Moreover, compared with the traditional proportional integral derivative control, this method is more effective.

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Ueno, Yuji, and Naoki Endo. "Application of Thermal Spray for Boiler." JAPAN TAPPI JOURNAL 66, no. 5 (2012): 491–93. http://dx.doi.org/10.2524/jtappij.66.491.

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Yang, Jian Meng, Wang Wei, and Nian Zhe Qi. "Exergy Analysis of 330MW Thermal Power Unit." Applied Mechanics and Materials 246-247 (December 2012): 505–8. http://dx.doi.org/10.4028/www.scientific.net/amm.246-247.505.

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This paper took one 330MW unit boiler in one power plant as an example, then doing some research about the boiler system energy change through doing exergy analysis. After this, the exergy flow equation was established, the energy transfer, utilize and loss of the thermal power plant production was revealed, the exergy efficiency of the boiler was defined. So the paper can provide a basis for energy utilization of power plant.

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Zima, Wiesław, Sławomir Grądziel, and Artur Cebula. "Modelling of heat and flow phenomena occuring in waterwall tubes of boilers for supercritical steam parameters." Archives of Thermodynamics 31, no. 3 (September 1, 2010): 19–36. http://dx.doi.org/10.2478/v10173-010-0012-y.

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Modelling of heat and flow phenomena occuring in waterwall tubes of boilers for supercritical steam parametersIn this paper a mathematical model enabling the analysis of the heat-flow phenomena occurring in the waterwalls of the combustion chambers of the boilers for supercritical parameters is proposed. It is a one-dimensional model with distributed parameters based on the solution of equations describing the conservation laws of mass, momentum, and energy. The purpose of the numerical calculations is to determine the distributions of the fluid enthalpy and the temperature of the waterwall pipes. This temperature should not exceed the calculation temperature for particular category of steel. The derived differential equations are solved using two methods: with the use of the implicit difference scheme, in which the mesh with regular nodes was applied, and using the Runge-Kutta method. The temperature distribution of the waterwall pipes is determined using the CFD. All thermophysical properties of the fluid and waterwall pipes are computed in real-time. The time-spatial heat transfer coefficient distribution is also computed in the on-line mode. The heat calculations for the combustion chamber are carried out with the use of the zone method, thus the thermal load distribution of the waterwalls is known. The time needed for the computations is of great importance when taking into consideration calculations carried out in the on-line mode. A correctly solved one-dimensional model ensures the appropriately short computational time.

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Wang, Ding Hui, Bin Yang, Ya Feng Zhong, Bao Min Sun, Jing Xin, and Xiao Meng Chen. "Study on Computational Methods for the Refractory Belt Area of Coal Fired Boilers." Advanced Materials Research 773 (September 2013): 25–29. http://dx.doi.org/10.4028/www.scientific.net/amr.773.25.

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The worse coal quality cause low center flame temperature in furnace, low combustion stability, high carbon content in fly ash and slag. The refractory belt installed in primary combustion zone can reduce the heat absorption capacity of water wall and improve the average temperature to steady ignition and high efficient combustion. For conforming the area of refractory belt better, the equation was founded by thermal computational methods and analyzing the different influence to the area of refractory belt.

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Zhu, Rui, and Jian Xing Ren. "Numerical Analysis of Stress and Temperature Coupled Field for Boiler Superheater in Thermal Power Plant." Applied Mechanics and Materials 241-244 (December 2012): 2139–43. http://dx.doi.org/10.4028/www.scientific.net/amm.241-244.2139.

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Boiler failure is the main power plant boiler operation fault. And boiler superheater tube is one of the important reasons for boiler failure, which affects the safe and stable operation of power generation equipment. Structure design and calculation of boiler superheater has important influence on performance and life of boiler, so three-dimensional structural model of boiler superheater is built in this paper. Based on the finite element method boiler superheater in temperature and stress coupled field are analyzed. The highest temperature, maximum stress, and distribution characteristics of stress and temperature couple field of boiler superheater including straight and elbow section are computed. The date on the actual operation of a power plant was used in the process of analysis. And thermal physics and mechanical properties of the boiler superheater tube were taken full consideration. It provides a reliable basis for reasonable design and safety evaluation of the boiler superheater.

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Wu, Qinghong. "Computer image processing and neural network technology for boiler thermal energy diagnosis." Thermal Science 24, no. 5 Part B (2020): 3059–68. http://dx.doi.org/10.2298/tsci191012080w.

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The paper uses the flame image processing technology to diagnose the furnace flame combustion achieve the measurement of boiler heat energy. The paper obtains the combustion image of the flame image processing system, and extracts the flame image characteristics of the boiler thermal energy diagnosis, constructs the neural network model of the boiler thermal energy diagnosis, and trains and tests the extracted flame image feature parameter values as the input of the neural network. A rough diagnosis of the boiler?s thermal energy is obtained while predicting the state of combustion. According to the research results, a boiler thermal energy diagnosis system was designed and tested on the boiler of 200 MW unit. The experimental results confirmed the applicability of the system, which can realize on-line monitoring of boiler heat energy and evaluate the combustion situation.

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Haiqian, Zhao, Liu Xiaoyan, Liu Lijun, Wu Yongning, Li Xiaohui, and Zhou Ying. "Study on New Thermal Insulation Construction of Thermal Recovery Boiler." Energy Procedia 16 (2012): 1466–71. http://dx.doi.org/10.1016/j.egypro.2012.01.231.

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Braga, Camila Soares, Valéria Antônia Justino Rodrigues, Julio César Costa Campos, Amaury Paulo de Souza, Luciano José Minette, Angêlo Casali de Moraes, and Guilherme Luciano Sensato. "Evaluation of thermal overload in boiler operators." Work 41 (2012): 470–75. http://dx.doi.org/10.3233/wor-2012-0198-470.

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AOI, Shingo, Ryuichiro EBARA, Takashi NISHIMURA, and Hiroyuki TOKUNAGA. "Thermal Fatigue Behavior of Boiler Tube Steel." Proceedings of the JSME annual meeting 2003.1 (2003): 155–56. http://dx.doi.org/10.1299/jsmemecjo.2003.1.0_155.

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Wang, Jinwei, Xinmu Zhao, Yu Wang, Xing Xing, Jiansheng Zhang, and Guangxi Yue. "Thermal boundary layer in CFB boiler riser." China Particuology 4, no. 3-4 (July 2006): 131–35. http://dx.doi.org/10.1016/s1672-2515(07)60252-8.

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Balasevicius, Leonas, Gintaras Dervinis, Vidmantas Macerauskas, and Vilmantas Zukauskas. "A26: Steam boiler thermal environment protection system." IFAC Proceedings Volumes 37, no. 20 (November 2004): 147–52. http://dx.doi.org/10.1016/s1474-6670(17)30587-6.

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Journal articles on the topic 'Thermal computation of boiler'

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