Готові списки джерел за темами / Eddy dissipation concept (EDC)

Добірка наукової літератури з теми "Eddy dissipation concept (EDC)"

Автор: Grafiati

Опубліковано: 10 грудня 2022

Оновлено: 28 січня 2023

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Статті в журналах з теми "Eddy dissipation concept (EDC)"

Bösenhofer, Markus, Eva-Maria Wartha, Christian Jordan, and Michael Harasek. "The Eddy Dissipation Concept—Analysis of Different Fine Structure Treatments for Classical Combustion." Energies 11, no. 7 (July 20, 2018): 1902. http://dx.doi.org/10.3390/en11071902.

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The Eddy Dissipation Concept (EDC) is common in modeling turbulent combustion. Several model improvements have been proposed in literature; recent modifications aim to extend its validity to Moderate or Intense Low oxygen Dilution (MILD) conditions. In general, the EDC divides a fluid into a reacting and a non-reacting part. The reacting part is modeled as perfectly stirred reactor (PSR) or plug flow reactor (PFR). EDC theory suggests PSR treatment, while PFR treatment provides numerical advantages. Literature lacks a thorough evaluation of the consequences of employing the PFR fine structure treatment. Therefore, these consequences were evaluated by employing tests to isolate the effects of the EDC variations and fine structure treatment and by conducting a Sandia Flame D modeling study. Species concentration as well as EDC species consumption/production rates were evaluated. The isolated tests revealed an influence of the EDC improvements on the EDC rates, which is prominent at low shares of the reacting fluid. In contrast, PSR and PFR differences increase at large fine fraction shares. The modeling study revealed significant differences in the EDC rates of intermediate species. Summarizing, the PFR fine structure treatment might be chosen for schematic investigations, but for detailed investigations a careful evaluation is necessary.

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Shen, Bin Xian, and Wei Qiang Liu. "Numerical Simulation of Turbulence-Chemical Interaction Models on Combustible Particle MILD Combustion." Advanced Materials Research 1070-1072 (December 2014): 1752–57. http://dx.doi.org/10.4028/www.scientific.net/amr.1070-1072.1752.

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Typical combustible particle coal has been analyzed by using turbulence-chemistry interaction models to realize which models are more accurate and reasonable on pulverized coal MILD combustion. Three turbulence-chemistry interaction models are examined: the Equilibrium Mixture Fraction/PDF (PDF), the Eddy Break Up (EBU), the Eddy Dissipation Concept (EDC). All of three models can give a suitable prediction of axial velocity on combustible particle coal MILD combustion because turbulence-chemistry interaction models have little influence on flow field and flow structure. The Eddy Dissipation Concept model (EDC), based on advanced turbulence-chemistry interaction with global and detailed kinetic mechanisms can produce satisfactory results on chemical and fluid dynamic behavior of combustible particle coal MILD combustion, especially on temperature and species concentrations.

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Martinez-Sanchis, Daniel, Andrej Sternin, Jaroslaw Shvab, Oskar Haidn, and Xiangyu Hu. "An Eddy Dissipation Concept Performance Study for Space Propulsion Applications." Aerospace 9, no. 9 (August 27, 2022): 476. http://dx.doi.org/10.3390/aerospace9090476.

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In this study, Direct Numerical Simulations (DNS) of a turbulent diffusion flame are conducted to investigate the performance of the Eddy Dissipation Concept in turbulent combustion for space propulsion applications. A 20-bar methane-oxygen diffusion flame is simulated to resemble the conditions encountered in modern rocket combustors. The numerical simulations were conducted using the software EBI-DNS within the OpenFOAM framework. An approach for analysis and validation of the combustion model with DNS is developed. The EDC model presents a good agreement with DNS observations in the most prevalent species. Nevertheless, the EDC struggles to predict the mean chemical production rate of intermediate species. It is found that local adaption of the model constants is essential for maximizing the prediction capabilities. The relationship of these parameters with the Reynolds number and the Damköhler number are mostly in good agreement with the trends proposed in recent research .

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He, Di, Yusong Yu, Hao Ma, Hongbo Liang, and Chaojun Wang. "Extensive Discussions of the Eddy Dissipation Concept Constants and Numerical Simulations of the Sandia Flame D." Applied Sciences 12, no. 18 (September 13, 2022): 9162. http://dx.doi.org/10.3390/app12189162.

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The indisputable wide use of the Eddy Dissipation Concept (EDC) implies that the resulting mean reaction rate is reasonably well modeled. To model turbulent combustions, an amount of EDC constants that differ from the original values was proposed. However, most of them were used without following the nature of the model or considering the effects of the modification. Starting with the energy cascade and the EDC models, the exact original primary and secondary constants are deduced in detail in this work. The mean reaction rate is then formulated from the primary constants or the secondary constants. Based on the physical meaning of fine structures, the limits of the EDC constants are presented and can be used to direct the EDC constant modifications. The effects of the secondary constant on the mean reaction rate are presented and the limiting turbulence Reynolds number used for the validity of EDC is discussed. To show the effects of the constants of the EDC model on the mean reaction rate, 20 combinations of the primary constants are used to simulate a laboratory-scale turbulent jet flame, i.e., Sandia Flame D. After a thorough and careful comparison with experiments, case 8, with a secondary constant of 6 and primary constants of 0.1357 and 0.11, can aptly reproduce this flame, except for in the over-predicted mean OH mass fraction.

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Ertesvåg, Ivar S. "Analysis of Some Recently Proposed Modifications to the Eddy Dissipation Concept (EDC)." Combustion Science and Technology 192, no. 6 (May 5, 2019): 1108–36. http://dx.doi.org/10.1080/00102202.2019.1611565.

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Kuang, Yucheng, Boshu He, Chaojun Wang, Wenxiao Tong, and Di He. "Numerical analyses of MILD and conventional combustions with the Eddy Dissipation Concept (EDC)." Energy 237 (December 2021): 121622. http://dx.doi.org/10.1016/j.energy.2021.121622.

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Fukumoto, Kazui, and Yoshifumi Ogami. "Simulation of CO-H2-Air Turbulent Nonpremixed Flame Using the Eddy Dissipation Concept Model with Lookup Table Approach." Journal of Combustion 2012 (2012): 1–11. http://dx.doi.org/10.1155/2012/496460.

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We present a new combustion simulation technique based on a lookup table approach. In the proposed technique, a flow solver extracts the reaction rates from the look-up table using the mixture fraction, progress variable, and reaction time. Look-up table building and combustion simulation are carried out simultaneously. The reaction rates of the chemical species are recorded in the look-up table according to the mixture fraction, progress variable, and time scale of the reaction. Once the reaction rates are recorded, a direct integration to solve the chemical equations becomes unnecessary; thus, the time for computing the reaction rates is shortened. The proposed technique is applied to an eddy dissipation concept (EDC) model and it is validated through a simulation of a CO-H2-air nonpremixed flame. The results obtained by using the proposed technique are compared with experimental and computational data obtained by using the EDC model with direct integration. Good agreement between our method and the EDC model and the experimental data was found. Moreover, the computation time for the proposed technique is approximately 99.2% lower than that of the EDC model with direct integration.

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Sedano, Camilo, Omar López, Alexander Ladino, and Felipe Muñoz. "Prediction of a methane circular pool fire with fireFoam." MATEC Web of Conferences 240 (2018): 05026. http://dx.doi.org/10.1051/matecconf/201824005026.

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In the present work, the fireFoam solver was used with Large Eddy Simulation (LES) and the Eddy Dissipation Concept (EDC) for modelling a medium-scale methane pool fire. A convergence analysis performed, showed that a 2 Million elements three-dimensional mesh, is good enough to attain good numerical results. By comparing the numerical results obtained, with the experimental ones, as well as numerical results from previous studies, it was proven that the fireFoam solver is able to obtain satisfactory results.

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Ali, Akram Ben, Mansour Karkoub, and Mouldi Chrigui. "Numerical Investigation of Turbulent Premixed Combustion of Methane / Air in Low Swirl Burner under Elevated Pressures and Temperatures." International Journal of Heat and Technology 39, no. 1 (February 28, 2021): 155–60. http://dx.doi.org/10.18280/ijht.390116.

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Turbulent combustion modeling of lean premixed methane/air gas mixture in a low swirl burner is carried out using Large Eddy Simulation (LES). The operating conditions of the experiment as well as simulation are carried out at elevated pressure and temperature. The first case-simulation is a premixed combustion model based on C-equation formulation, the second one is based on species transport – Eddy Dissipation Concept (EDC) model. Numerical results for axial velocity and turbulence intensity along the centerline showed a good agreement against the experimental data. Quantitative results of OH mass fraction contour showing the flame structure are in a plausible agreement compared to the experimental measurement.

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Sedano, Camilo Andrés, Omar Darío López, Alexander Ladino, and Felipe Muñoz. "Prediction of a Small-Scale Pool Fire with FireFoam." International Journal of Chemical Engineering 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/4934956.

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A computational model using Large Eddy Simulation (LES) for turbulence modelling was implemented, by means of the Eddy Dissipation Concept (EDC) combustion model using the fireFoam solver. A small methanol pool fire experiment was simulated in order to validate and compare the numerical results, hence trying to validate the effectiveness of the solver. A detailed convergence analysis is performed showing that a mesh of approximately two million elements is sufficient to achieve satisfactory numerical results (including chemical kinetics). A good agreement was achieved with some of the experimental and previous computational results, especially in the prediction of the flame height and the average temperature contours.

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Дисертації з теми "Eddy dissipation concept (EDC)"

CURSINO, Gustavo Gomes Sampaio. "Influência da geometria da distribuição de temperatura em um combustor vertical de leito fluidizado a óleo combustível." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/309.

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Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-03-23T01:44:32Z No. of bitstreams: 1 GUSTAVO GOMES SAMPAIO CURSINO - TESE PPGEQ 2016.pdf: 5939681 bytes, checksum: 518baf4150ea2fb7085706252276b9fa (MD5)
Made available in DSpace on 2018-03-23T01:44:32Z (GMT). No. of bitstreams: 1 GUSTAVO GOMES SAMPAIO CURSINO - TESE PPGEQ 2016.pdf: 5939681 bytes, checksum: 518baf4150ea2fb7085706252276b9fa (MD5) Previous issue date: 2016-04-18
Este trabalho teve o propósito de determinar o comportamento dos gases na seção de radiação de um combustor de ar que pertence a uma planta industrial. O corpo metálico do equipamento rompeu em seu primeiro ano de operação, devido a um problema conceitual em sua geometria. A fluidodinâmica computacional (CFD), por meio do método dos volumes finitos, foi utilizada para desenvolver um modelo tridimensional que pudesse reproduzir o perfil de temperatura e o comportamento do fluxo do ar de combustão no equipamento. Na simulação, através do uso do software ANSYS CFX, foram utilizados: (i) o modelo de turbulência Reynolds Stress Model (RSM); (ii) as malhas hexaédrica, tetraédrica e prismática; (iii) o modelo de radiação P-1; e (iv) o modelo de combustão Eddy Dissipation Concept (EDC). Como resultado, foram apresentadas quatro possíveis mudanças na geometria do combustor de ar que, caso adotadas, eliminariam os riscos de novas falhas e garantiriam a continuidade operacional da unidade de processo.
This paper has the objective to describe the behavior of the flow and temperature of the flue gas in the radiation section of the vessel used to preheat air in a combustor. The equipment failed in its first operational year, due to a conceptual problem in its geometry. The CFD code based on finite volume method was applied to simulate the physical model of combustor using the ANSYS CFX software, reproducing the main features of the preheater. The simulation had considered: (i) Reynolds Stress Model (RSM) as turbulence model, (ii) The meshes applied were the hexahedral, tetrahedral and prismatic, (iii) P-1 was used as the radiation model and (iv) Eddy Dissipation Concept (EDC) as combustion model. Through the simulation was possible to propose four different kind of combustor geometry modification, that the application of anyone of them would eliminate the risk of new failures, ensuring the unit production availability.

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Chen, Zhibin. "Extension of the eddy dissipation concept and laminar smoke point soot model to the large eddy simulation of fire dynamics." Thesis, Kingston University, 2012. http://eprints.kingston.ac.uk/24031/.

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The original turbulent energy cascade of eddy dissipation concept (EDC) has been extended to the LES framework, assuming that there is always a structure level on which the typical length scale is equivalent to the filter width of large eddy simulation (LES). The velocity scale on this structure level could be calculated from the sub-grid scale (SGS) kinetic energy, provided that this kinetic energy transport equation is solved in LES. All other quantities would thus be calculated on this structure level according to the general formulations from the original turbulent energy cascade. Based on this known structure level, the total kinetic energy and dissipation rate could be estimated with the integral length scale being assumed to be equivalent to the characteristic length of fire plume. Consequently, the Kolmogorov time scale and the integral time scale could also be calculated and then applied in the soot model development. The laminar based smoke point soot model (SPSM) is also extended to the LES framework. The filtered soot mass fraction transport equation is solved with the thermophoresis term neglected. The filtered soot formation rate is treated using the concept of partially stirred reactor (PaSR). This rate is thus associated with the laminar based soot formation rate substituted with the filtered properties through the expression of K. Note that in K the soot formation chemical time scale is assumed to be proportional to the laminar smoke point height (SPH) while its turbulent mixing time is supposed to be the. geometric mean of the Kolmogorov time scale and integral time scale. Furthermore, a new soot oxidation model is developed by imitating the gas phase combustion model, i.e. EDC, as the soot particles are assumed to be the solid phase of the fuel. Note that the turbulent mixing time scale for soot oxidation has been chosen to be the same as soot formation. The soot formation and oxidation models are coupled to treat the effect of soot on the fuel distribution and energy transport. The approaches to calculate flame height, radiative fraction, and surface emissive power (SEP) have also been developed for sooty flames. The models and approaches mentioned above are implemented into FireFOAM, which is a fully compressible solver based on the platform of OpenFOAM. A series of fire scenarios, involved with different fuels including methanol, methane, heptane and toluene, and with different scales ranging from 30 em to 56 m, are performed for validation studies. The detailed comparisons, such as mean velocity and its fluctuation, mean temperature and its fluctuation, soot volume fraction and its fluctuation, turbulent heat flux, time scales and length scales, flame height, radiative fraction, SEP and so on, between predictions and measurements demonstrate the capability of the current models.

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Evans, Michael J. "Flame Stabilisation in the Transition to MILD Combustion." Thesis, 2017. http://hdl.handle.net/2440/119081.

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Emissions reduction and energy management are current and future concerns for governments and industries alike. The primary source of energy worldwide for electricity, air transport and industrial processes is combustion. Moderate or intense low oxygen dilution (MILD) combustion offers improved thermal efficiency and a significant reduction of CO and NOx pollutants, soot and thermo-acoustic instabilities compared to conventional combustion. Whilst combustion in the MILD regime offers considerable advantages over conventional combustion, neither the structure of reacting jets under MILD conditions, nor the boundaries of the MILD regime are currently well understood. This work, therefore, serves to fill this gap in the understanding of flame structure near the boundaries of the MILD regime. The MILD combustion regime has been previously investigated experimentally and numerically in premixed reactors and non-premixed flames. In this study, definitions of MILD combustion are compared and contrasted, with the phenomenological premixed description of MILD combustion extended to describe non-premixed flames. A simple criterion is derived analytically which offers excellent agreement with observations of previously studied cases and new, non-premixed MILD and autoignitive flames presented in this work. This criterion facilitates a simple, predictive approach to distinguish MILD combustion, autoignitive flames, and the transition between the two regimes. The adequacy of simplified reactors as a tool for predicting non-premixed ignition behaviour in the transition between MILD combustion and autoignition has not previously been resolved, and is addressed in this work. The visual lift-off behaviour seen in the transition between MILD combustion and conventional autoignitive flames seen experimentally is successfully replicated using simplified reactors. The location of the visible flame base in a jet-in-hot-coflow burner is shown to be highly sensitive to the relative location of the most reactive mixture fraction and the high strain-rate shear layer due to the strong coupling of between ignition chemistry and the underlying flow-field. Previous studies have demonstrated a strong dependence of ignition delay times to significant concentrations of minor species. Simulations presented in this work demonstrate that small concentrations of the hydroxyl radical (OH), similar to those expected in practical environments, significantly affect ignition delay and intensity of non-premixed MILD combustion, however have little effect on autoignitive flames. Importantly, such concentrations of OH do not result in a change in flame structure for the cases investigated. Whilst these results stress the importance of minor species in modelling the transient ignition of non-premixed MILD combustion, steady-state simulations do not demonstrate the same sensitivity to concentrations of minor species expected in hot combustion products. These results suggest that the temperature and oxygen concentration in the oxidant stream are the most important factors governing the boundaries of, the MILD combustion regime. Investigations of reaction zone structure and ignition in, and near the boundaries of, the MILD combustion regime have demonstrated the relative importance of different aspects of ambient conditions and differences in structure between non-premixed MILD and autoignitive flames. These findings build upon the understanding of this regime and provide critical insight for future studies towards both fundamental research, and the practical implementation, of MILD combustion.
Thesis (Ph.D.) -- University of Adelaide, School of Mechanical Engineering, 2017

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Misztal, Tomasz. "Badanie emisji NO podczas spalania oleju w warunkach wysokotemperaturowego podgrzewu powietrza spalania." Rozprawa doktorska, 2005. https://repolis.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=5056.

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Misztal, Tomasz. "Badanie emisji NO podczas spalania oleju w warunkach wysokotemperaturowego podgrzewu powietrza spalania." Rozprawa doktorska, 2005. https://delibra.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=5056.

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Частини книг з теми "Eddy dissipation concept (EDC)"

Manescau, Brady, Khaled Chetehouna, Ilyas Sellami, Rachid Nait-Said, and Fatiha Zidani. "BLEVE Fireball Effects in a Gas Industry: A Numerical Modeling Applied to the Case of an Algeria Gas Industry." In Fire Safety and Management Awareness. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.92990.

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This chapter presents the numerical modeling of the BLEVE (Boiling Liquid Expanding Vapor Explosion) thermal effects. The goal is to highlight the possibility to use numerical data in order to estimate the potential damage that would be caused by the BLEVE, based on quantitative risk analysis (QRA). The numerical modeling is carried out using the computational fluid dynamics (CFD) code Fire Dynamics Simulator (FDS) version 6. The BLEVE is defined as a fireball, and in this work, its source is modeled as a vertical release of hot fuel in a short time. Moreover, the fireball dynamics is based on a single-step combustion using an eddy dissipation concept (EDC) model coupled with the default large eddy simulation (LES) turbulence model. Fireball characteristics (diameter, height, heat flux and lifetime) issued from a large-scale experiment are used to demonstrate the ability of FDS to simulate the various steps of the BLEVE phenomenon from ignition up to total burnout. A comparison between BAM (Bundesanstalt für Materialforschung und –prüfung, Allemagne) experiment data and predictions highlights the ability of FDS to model BLEVE effects. From this, a numerical study of the thermal effects of BLEVE in the largest gas field in Algeria was carried out.

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Wartha, Eva-Maria, Markus Bösenhofer, and Michael Harasek. "Computational Improvements for the Eddy Dissipation Concept by Operator Splitting and Tabulation." In Computer Aided Chemical Engineering, 1687–92. Elsevier, 2018. http://dx.doi.org/10.1016/b978-0-444-64235-6.50294-1.

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Тези доповідей конференцій з теми "Eddy dissipation concept (EDC)"

Yusuf, Uzair, Jehanzeb Masud, Usman Zia, Ibrahim Sher, Jawad Zakir, and Mohib Siddiqui. "Modelling of Supersonic Combustion using Finite-Rate Eddy-Dissipation (FRED) and Eddy-Dissipation Concept (EDC) Turbulence Chemistry Interaction (TCI) Models." In AIAA SCITECH 2023 Forum. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2023. http://dx.doi.org/10.2514/6.2023-1689.

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Fukumoto, Kazui, and Yoshifumi Ogami. "Simulation of H2-Air Turbulent Diffusion Flame by the Combustion Model Using Chemical Equilibrium Combined With the Eddy Dissipation Concept." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88429.

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This research aims at developing a turbulent diffusion combustion model based on the chemical equilibrium method and chemical kinetics for simplifying complex chemical mechanisms. This paper presents a combustion model based on the chemical equilibrium method and the eddy dissipation concept (CE-EDC model); the CE-EDC model is validated by simulating a H2-air turbulent diffusion flame. In this model, the reaction rate of fuels and intermediate species is estimated by using the equations of the EDC model. Further, the reacted fuels and intermediate species are assumed to be in chemical equilibrium; the amount of the other species is determined from the amount of the reacted fuels, intermediate species, and air as reactants by using the Gibbs free energy minimization method. An advantage of the CE-EDC model is that the amount of the combustion products can be determined without using detailed chemical mechanisms. The results obtained by using this model were in good agreement with the experimental and computational data obtained by using the EDC model. Using this model, the amount of combustion products can be calculated without using detailed chemical mechanisms. Further, the accuracy of this model is same as that of the EDC model.

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Yaga, Mitsuru, Kazutaka Suzuki, Hajime Endo, Tsuyoshi Yamamoto, Hideyuki Aoki, and Takatoshi Miura. "An Application of LES for Gas Turbine Combustor." In 2002 International Joint Power Generation Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/ijpgc2002-26119.

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A three-dimensional turbulence spray combustion simulation in a gas turbine combustor with Large Eddy Simulation is carried out. In this study, we construct a new eddy characteristic time model derived from a large-scale motion to estimate the combustion reaction rate with an eddy dissipation concept (EDC) model, and estimate combustion characteristics (temperature and chemical species distribution) in the gas turbine combustor for the purpose of validating this model. The essence of this model is that eddy characteristic time is estimated by considering Kolmogorov scale at first. From this assumption, eddy dissipation rate is apparent. However it is not solved directly in Large Eddy Simulation. So eddy dissipation rate is estimated by an assumption that turbulence energy generation and dissipation are locally equal (it is the same assumption as Smagorinsky model), and it is substituted in the eddy characteristic time formula. The overall reaction C12H24+18O2 → 12CO2+12H2O, is often used for turbulent combustion simulation for saving calculation time, but cannot consider CO and H2 formation in local fuel-rich region. To solve this problem, we use 3-step global mechanism (C12H24+6O2 → 12CO+12H2, CO+0.5O2 ↔ CO2, H2+0.5O2 ↔ H2O) to calculate turbulent non-premixed flame characteristics coupling with EDC. The calculated CO2 mole fraction distribution is in fairly good agreement with the experimental data. However, the calculated temperature distribution does not agree well with the measured result of temperature because of disturbing heat transport to downstream by dilution air jet. Though few problems are left, it is shown that the combustion simulation using LES with EDC model is effective method to calculate the characteristics of turbulent diffusion flame in furnace such as gas turbine combustor.

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Goldin, Graham M., Jens Madsen, Douglas L. Straub, William A. Rogers, and Kent H. Casleton. "Detailed Chemistry Simulations of a Trapped Vortex Combustor." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38780.

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Steady simulations of a Trapped Vortex Combustor are performed with the Strained Laminar Flamelet model, the Eddy Dissipation Concept (EDC) model and the Composition PDF Transport model using an accurate 19 species Augmented Reduced Mechanism. CO predictions are reasonable, although the EDC model over-predicts CO since the reaction time in the fine scales is less than the residence time in the combustor. The PDF Transport model over-predicts NO by a factor of four for reasons that are not well understood at present. In-situ Adaptive Tabulation (ISAT) accelerates chemistry calculations by two to three orders of magnitude, making 3D CFD calculations with detailed chemistry computationally feasible.

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Fukumoto, Kazui, and Yoshifumi Ogami. "Simulation of a CO-H2-Air Turbulent Diffusion Flame by the Chemical Equilibrium Method With a Few Chemical Reactions." In ASME 2008 Heat Transfer Summer Conference collocated with the Fluids Engineering, Energy Sustainability, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/ht2008-56286.

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The aim of our research is to build a model that can evaluate the amount of combustion products by using the chemical equilibrium method with a few chemical reactions. This paper presents an eddy dissipation concept/chemical equilibrium model (EDC/CE) and validates it by simulating a CO-H2 air turbulent diffusion flame. The obtained results were compared with Correa’s experimental data, Gran’s computational data, and the computational data obtained by using a chemical equilibrium model in FLUENT. An advantage of the EDC/CE model is that the amount of any combustion products are obtained without using detailed chemical mechanisms. The results obtained by the EDC/CE model are in good agreement with the reference data. With the combustion model that we have developed, the amount of combustion products can be calculated without detail chemical mechanisms, and the accuracy of this model is in the same order as that of the EDC model.

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Sloan, David G., and Geoffrey J. Sturgess. "Modeling of Local Extinction in Turbulent Flames." In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-433.

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The Eddy Dissipation Concept (EDC), proposed by Magnussen (1985), advances the concept that the reactants are homogeneously mixed within the fine eddy structures of turbulence and that the fine structures may therefore be regarded as perfectly stirred reactors (PSRs). To understand more fully the extent to which such a sub-grid scale stirred reactor concept could be applied within the context of a computational fluid dynamics (CFD) calculation to model local or global extinction phenomena: (1) various kinetic mechanisms are investigated with respect to CPU penalty and predictive accuracy in comparisons with stirred reactor lean blowout (LBO) data and (2) a simplified time-scale comparison, extracted from the EDC model and applied locally in a fast-chemistry CFD computation is evaluated with respect to its capabilities to predict attached and lifted flames. Comparisons of kinetic mechanisms with PSR lean blowout data indicate severe discrepancies in the predictions with the data and with each other. Possible explanations are delineated and discussed. Comparisons of the attached and lifted flame predictions with experimental data are presented for some benchscale burner cases. The model is only moderately successful in predicting lifted flames and fails completely in the attached flame case. Possible explanations and research avenues are reviewed and discussed.

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Jella, Sandeep, Pierre Gauthier, Gilles Bourque, Jeffrey Bergthorson, Ghenadie Bulat, Jim Rogerson, and Suresh Sadasivuni. "Large Eddy Simulations of a Pressurized, Partially-Premixed Swirling Flame With Finite-Rate Chemistry." In ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-65256.

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Finite-rate chemical effects at gas turbine conditions lead to incomplete combustion and well-known emissions issues. Although a thin flame front is preserved on an average, the instantaneous flame location can vary in thickness and location due to heat losses or imperfect mixing. Post-flame phenomena (slow CO oxidation or thermal NO production) can be expected to be significantly influenced by turbulent eddy structures. Since typical gas turbine combustor calculations require insight into flame stabilization as well as pollutant formation, combustion models are required to be sensitive to the instantaneous and local flow conditions. Unfortunately, few models that adequately describe turbulence-chemistry interactions are tractable in the industrial context. A widely used model capable of employing finite-rate chemistry, is the Eddy Dissipation Concept (EDC) model of Magnussen. Its application in large eddy simulations (LES) is problematic mainly due to a strong sensitivity to the model constants which were based on an isotropic cascade analysis in the RANS context. The objectives of this paper are: (i) To formulate the EDC cascade idea in the context of LES; and (ii) To validate the model using experimental data consisting of velocity (PIV measurements) and major species (1-D Raman measurements), at four axial locations in the near-burner region of a Siemens SGT-100 industrial gas turbine combustor.

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Stro¨hle, Jochen, Tore Myhrvold, and Nils A. Ro̸kke. "A Numerical Evaluation of Different Oxy-Fuel Concepts for a Gas Turbine Combustor." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53440.

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In the present study, a numerical evaluation of different oxy-fuel concepts for a typical gas turbine combustor is performed to investigate how the inlet conditions affect fuel and CO burnout, NOx and soot emissions, and wall heat fluxes. Three oxy-fuel cases with different distribution of oxygen to the inlets are compared with a reference case using air as an oxidiser. Three-dimensional numerical simulations are performed using the in-house CFD code SPIDER. Turbulent combustion is modelled by the Eddy Dissipation Concept (EDC) with detailed chemistry and soot formation reactions. Whereas low oxygen concentrations at the fuel inlet lead to extinction of the flame, the temperature in the primary combustion zone becomes very high leading to unacceptable wall heat fluxes at high oxygen concentrations. NOx, hydrocarbons and soot emissions are very low while CO emissions are relatively high for the oxy-fuel cases.

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Wang, F., Y. Huang, and Y. Z. Wu. "Simulation of Methanol-Air Two-Phase Flames Using Various Turbulent Combustion Models." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59344.

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Though fossil fuel is running out, liquid fuels nowadays still provide the most energy used by industrial furnaces, automotive and aero engines. How to predict a two-phase turbulent combustion flame is still a big problem to designers. Generally, the liquid fuel is sprayed and mixed with oxygen, and the flame characteristics depends on the fuel atomization, the fuel droplet spatial distribution, and its interaction with the turbulent oxidizer flow field: turbulent heat, mass and momentum transfer, complicated chemical kinetics, and turbulent-chemistry interaction. Turbulent combustion model is a key point for the two phase combustion simulation. For its short time consuming, Reynolds Averaged Navier Stokes (RANS) method nowadays still is the major tool for gas turbine chamber (GTC) designers, but there is not a universal method in RANS GTC spray combustion simulation at present especially for the two-phase turbulent combustion. The Eddy-Break-Up turbulent combustion model (EBU), Eddy Dissipation Concept turbulent combustion model (EDC), steady Laminar Flame-let turbulent combustion Model (LFM) and the Composition PDF transport turbulent combustion model (CPDF) are all widely used models. In this paper, these four turbulent models are used to simulate a methane-air turbulent jet flame measured by Sandia Lab first, then three methanol-air two-phase turbulent flames, in order to know the ability of these turbulent models. In the gas turbulent jet flame simulation, the result of LFM model and CPDF model are in better agreement with the experimental data than those of the EBU and the EDC models’ results. The reason is that the EBU model and EDC model are overestimated the effect of turbulent. In the three different cases of the two phase combustion simulation, CPDF is the best. The prediction ability of the other three models is different in different cases. The EDC predictions are closer to the experimental data when the air flow rate value is lower, whereas the LFM predictions are better when the air flow rate value is higher.

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Ghasemi, E., Soheil Soleimanikutanaei, and Cheng-Xian Lin. "Control of Turbulent Combustion Flow Inside a Gas Turbine Combustion Chamber Using Plasma Actuators." In ASME 2015 Power Conference collocated with the ASME 2015 9th International Conference on Energy Sustainability, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/power2015-49499.

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In this paper, effects of a standard plasma actuator on non-premixed turbulent reacting flows in a unique gas turbine combustion chamber have been studied numerically. The computational simulation is conducted by employing the Reynolds Averaged Navier-Stokes (RANS) approach. Chemical reaction kinetics has been modeled using the eddy dissipation concept (EDC) model. The numerical simulation has been carried out by Finite Element Methods. High voltage potential between two copper electrodes separated by a dielectric material has been applied which leads to the generation of plasma and an electric field, which creates a body force. It was found that by orienting the plasma force in the desired direction, combustion rate can be accelerated or controlled. The numerical results have been presented through velocity, temperature, and species concentration profiles under different combustion conditions.

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