Best Practice Advice AC2-10: Difference between revisions
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==Application Uncertainties, Computational Domain and Boundary Conditions== | ==Application Uncertainties, Computational Domain and Boundary Conditions== | ||
==Physical Modeling, Numerics and Recommendations== | ==Physical Modeling, Numerics and Recommendations== | ||
From experience and previous studies in the literature, it is quite obvious that the intrinsic unsteadiness and anisotropy of the flow field in IC engines renders scale-resolving approaches such as LES more suitable than RANS for the numerical simulation of such configurations, even though the high computational costs remain a real issue for routine design and optimization procedures. | |||
Three simulations of the same test case were presented. However, a direct comparison is challenging because | |||
*there are many differences between the simulations concerning physical models and numerical approaches and | |||
*the in-cylinder flow processes are coupled non-linearly. | |||
==Recommendations for future work== | ==Recommendations for future work== | ||
The presented experimental and simulation work revealed several open issues within IC-engine simulations as discussed in subsections \ref{sec:uncertainties} and \ref{sec:recommendations} which can be summarized as follows: | The presented experimental and simulation work revealed several open issues within IC-engine simulations as discussed in subsections \ref{sec:uncertainties} and \ref{sec:recommendations} which can be summarized as follows: | ||
Revision as of 14:39, 9 October 2018
Internal combustion engine flows for motored operation
Application Challenge AC2-10 © copyright ERCOFTAC 2024
Best Practice Advice
Key Fluid Physics
Application Uncertainties, Computational Domain and Boundary Conditions
Physical Modeling, Numerics and Recommendations
From experience and previous studies in the literature, it is quite obvious that the intrinsic unsteadiness and anisotropy of the flow field in IC engines renders scale-resolving approaches such as LES more suitable than RANS for the numerical simulation of such configurations, even though the high computational costs remain a real issue for routine design and optimization procedures.
Three simulations of the same test case were presented. However, a direct comparison is challenging because
- there are many differences between the simulations concerning physical models and numerical approaches and
- the in-cylinder flow processes are coupled non-linearly.
Recommendations for future work
The presented experimental and simulation work revealed several open issues within IC-engine simulations as discussed in subsections \ref{sec:uncertainties} and \ref{sec:recommendations} which can be summarized as follows:
- Further research is needed on robust and accurate numerical schemes for engine LES.
- Many models were originally developed for RANS applications and were subsequently adapted for LES. A thorough comparison of such physical models is needed to give clear recommendations which models or model combinations are best suited.
- There is still a lack of accurate boundary layer models for momentum and heat transfer.
References
Contributed by: Carl Philip Ding,Rene Honza, Elias Baum, Andreas Dreizler — Fachgebiet Reaktive Strömungen und Messtechnik (RSM),Technische Universität Darmstadt, Germany
Contributed by: Brian Peterson — School of Engineering, University of Edinburgh, Scotland UK
Contributed by: Chao He , Wibke Leudesdorff, Guido Kuenne, Benjamin Böhm, Amsini Sadiki, Johannes Janicka — Fachgebiet Energie und Kraftwerkstechnik (EKT), Technische Universität Darmstadt, Germany
Contributed by: Peter Janas, Andreas Kempf — Institut für Verbrennung und Gasdynamik (IVG), Lehrstuhl für Fluiddynamik, Universität Duisburg-Essen, Germany
Contributed by: Stefan Buhl, Christian Hasse — Fachgebiet Simulation reaktiver Thermo-Fluid Systeme (STFS), Technische Universität Darmstadt, Germany; former: Professur Numerische Thermofluiddynamik (NTFD), Technische Universität Bergakademie Freiberg, Germany
© copyright ERCOFTAC 2018