| 1. |
- Arshad, Salman, 1987, et al.
(författare)
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Subgrid Reaction-Diffusion Closure for Large Eddy Simulations Using the Linear-Eddy Model
- 2019
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Ingår i: Flow, Turbulence and Combustion. - : Springer Science and Business Media LLC. - 1573-1987 .- 1386-6184. ; 103:2, s. 389-416
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Tidskriftsartikel (refereegranskat)abstract
- Turbulent combustion models approximate the interaction between turbulence, molecular transport and chemical reactions. Among the many available turbulent combustion models, the present focus is the linear-eddy model (LEM) used as a subgrid combustion model for large eddy simulations. In particular this paper introduces a new LEM closure with the reaction-rate approach to close the filtered chemical source terms in the governing equations for species mass fractions and enthalpy. The new approach is tested using a non-premixed syngas flame and a bluff-body stabilized premixed flame problem. Simulation results are compared to data from a direct numerical simulation and experiments. This comparison shows that mean and rms quantities compare well with experiments and are in the range of previous simulation studies. These results are obtained with a pressure-based and unstructured computational-fluid-dynamics solver, an approach that is preferred in industry.
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| 2. |
- Gonzalez-Juez, Esteban D., et al.
(författare)
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Effect of the turbulence modeling in large-eddy simulations of nonpremixed flames undergoing extinction and reignition
- 2017
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Ingår i: AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting. - Reston, Virginia : American Institute of Aeronautics and Astronautics.
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Konferensbidrag (refereegranskat)abstract
- Simulating practical combustion systems requires the approximation of the interaction between turbulence, molecular transport and chemical reactions. Turbulent combustion models are used for this purpose, but their behavior is difficult to anticipate based on their mathematical formulations, making the use of numerical experimentation necessary. Therefore, the present work explores the effect of three turbulent-combustion models, two eddy-viscosity models, and their parameters on a combustion problem which is notoriously difficult to model: flame extinction and reignition. For this purpose, two types of temporal jets are considered, and direct-numerical-simulation results are compared qualitatively with those from large-eddy simulations.
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| 3. |
- Gonzalez-Juez, Esteban D., et al.
(författare)
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Turbulent-combustion closure for the chemical source terms and molecular mixing using the linear-eddy model
- 2017
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Ingår i: 53rd AIAA/SAE/ASEE Joint Propulsion Conference, 2017. - 9781624105111
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Konferensbidrag (refereegranskat)abstract
- Turbulent combustion models approximate the interaction between turbulence, molecular transport and chemical reactions with the purpose of allowing computationally feasible simulations. There are many of these models and the present interest is on the lineareddy model (LEM). Specifically this paper introduces and tests a new method to use LEM to close the filtered chemical source terms in the conservation equations of the thermochemical quantities. For this purpose, this paper discusses the conceptual enhancements of this method over traditional LEM implementations, and its testing in a widely-used bluff-body-stabilized-flame problem.
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