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Numerical Investigation of Turbulence Anisotropy of In-Cylinder Flows with Multi-Cycle Large Eddy Simulation
Technical Paper
2021-01-0416
ISSN: 0148-7191, e-ISSN: 2688-3627
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SAE WCX Digital Summit
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English
Abstract
In-cylinder flows in internal combustion engines are highly turbulent in nature. An important property of turbulence that plays a key role in mixture formation is anisotropy; it also influences ignition, combustion and emission formation. Thus, understanding the turbulence anisotropy of in-cylinder flows is critical. Since the most widely used two-equation Reynolds-averaged Navier-Stokes (RANS) turbulence models assume isotropic turbulence, they are not suitable for correctly capturing the anisotropic behavior of turbulence. However, large eddy simulation (LES) can account for the anisotropic behavior of turbulence.
In this paper, the Reynolds stress tensor (RST) is analyzed to assess the predictive capability of RANS and LES with regard to turbulence anisotropy. The influence of mesh size on turbulence anisotropy is also looked into for multi-cycle LES. Investigations were conducted to understand the anisotropic behavior of turbulence during the intake stroke of a single-cylinder optical research engine. Turbulence anisotropy has been visualized directly in the physical domain of engine with the help of componentality contours. The turbulence anisotropy predicted by RANS simulations confirms that it is completely influenced by the gradients of mean flow velocity as per the definition of RST according to the Boussinesq approximation, whereas LES captured the anisotropic behavior of turbulence. During the intake stroke, large structures such as the intake jet and the recirculation region are shown to have an effect on in-cylinder turbulence anisotropy. In addition, a comparison of coarse mesh LES with fine mesh LES revealed that the latter predicts more isotropic turbulence due to sub-grid modeling assumptions.
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Soni, R., Gößnitzer, C., Pirker, G., and Wimmer, A., "Numerical Investigation of Turbulence Anisotropy of In-Cylinder Flows with Multi-Cycle Large Eddy Simulation," SAE Technical Paper 2021-01-0416, 2021, https://doi.org/10.4271/2021-01-0416.Data Sets - Support Documents
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References
- Salazar , V. , and Kaiser , S. Influence of the Flow Field on Flame Propagation in a Hydrogen-fueled Internal Combustion Engine SAE International Journal of Engines 4 2 2376 2394 2011 https://doi.org/10.4271/2011-24-0098
- Kim , S.J. , Kim , Y.N. , and Lee , J.H. Analysis of the in-cylinder Flow, Mixture Formation and Combustion Processes in a Spray-Guided GDI Engine SAE Technical Paper 2008-01-0142 2008 https://doi.org/10.4271/2008-01-0142
- Goryntsev , D. 2007
- He , C. , Leudesdorff , W. , Di Mare , F. , Sadiki , A. , and Janicka , J. Analysis of In-cylinder Flow Field Anisotropy in IC Engine using Large Eddy Simulation Flow, Turbulence and Combustion 99 2 353 383 2017 10.1007/s10494-017-9812-3
- Zentgraf , F. , Baum , E. , Böhm , B. , Dreizler , A. , and Peterson , B. Analysis of the Turbulent in-cylinder Flow in an IC Engine using Tomographic and Planar PIV Measurements 17th International Symposium on Applications of Laser Techniques to Fluid Mechanics 7 10 2014
- Zentgraf , F. , Baum , E. , Böhm , B. , Dreizler , A. , and Peterson , B. On the Turbulent flow in Piston Engines: Coupling of Statistical Theory Quantities and Instantaneous Turbulence Physics of Fluids 28 4 2016
- Baum , E. , Peterson , B. , Böhm , B. , and Dreizler , A. On The Validation of LES Applied to Internal Combustion Engine Flows: Part 1: Comprehensive Experimental Database Flow, Turbulence and Combustion 92 1 269 297 2014 10.1007/s10494-013-9468-6
- MacDonald , J.R. and Fajardo , C.M. Turbulence Anisotropy Investigations in an Internal Combustion Engine ASME 978-0-7918-8403-4 2020 10.1115/ICEF2020-3029
- Bianchi , G.M. , Cantore , G. , Parmeggiani , P. , and Michelassi , V. On Application of Nonlinear k-ε Models for Internal Combustion Engine Flows Journal of Engineering for Gas Turbines and Power 124 3 668 677 2002 10.1115/1.1454115
- Emory , M.A. 2014
- Emory , B.M. , and Iaccarino , G. Visualizing Turbulence Anisotropy in the Spatial Domain with Componentality Contours Center for Turbulence Research Annual Research Briefs 123 137 2014
- Soni , R. , Gößnitzer , C. , Pirker , G. , and Wimmer , A. Visualization of Turbulence Anisotropy in the In-cylinder Flow of Internal Combustion Engines SAE Technical Paper 2020-01-1105 2020 https://doi.org/10.4271/2020-01-1105
- Pope , S.B. Turbulent Flows Cambridge Cambridge University Press 2000 10.1017/CBO9780511840531 9780521598866
- Germano , M. , Piomelli , U. , Moin , P. , and Cabot , W.H. A Dynamic Subgrid-scale Eddy Viscosity Model Physics of Fluids A: Fluid Dynamics 3 7 1760 1765 1991 10.1063/1.857955
- Dey , S. , Ravi Kishore , G. , Castro-Orgaz , O. , and Ali , S.Z. Turbulent Length Scales and Anisotropy in Submerged Turbulent Plane Offset Jets Journal of Hydraulic Engineering 145 2 2019 10.1061/(asce)hy.1943-7900.0001559
- Simonsen , A.J. Turbulent Stress Invariant Analysis: Clarification of Existing Terminology Physics of Fluids (December) 1 4 2004
- 2019
- Decan , G. , Broekaert , S. , Lucchini , T. , D’Errico , G. et al. Evaluation of Wall Heat Flux Calculation Methods for CFD Simulations of an Internal Combustion Engine Under Both Motored and HCCI Operation Applied Energy 232 451 461 2018
- Choi , K.S. , and Lumley , J.L. The Return to Isotropy of Homogeneous Turbulence Journal of Fluid Mechanics 436 59 84 2001 10.1017/S002211200100386X