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#1 |
New Member
kazuki
Join Date: Jan 2017
Posts: 5
Rep Power: 9 ![]() |
I examine in-cylinder gas flow of diesel engine with RANS model. However, I want to use LES model for improvement of accuracy. Please tell me what kind of LES model do you use for calculation of diesel engine.
Last edited by kazuki; November 13, 2018 at 00:24. |
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#2 |
New Member
Alireza Mashayekh
Join Date: Aug 2017
Location: Convergent Science, Madison WI
Posts: 14
Rep Power: 9 ![]() |
There are a few models implemented in CONVERGE for LES modeling. The first that we try is the DYNAMIC STRUCTURE model.
Please note that if you run your case w/ LES models but w/ the grid sized recommended for RANS simulations, your burning would be much slower; so, you have to significantly refine the mesh to get proper results w/ the LES models. Best, |
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#3 |
New Member
kazuki
Join Date: Jan 2017
Posts: 5
Rep Power: 9 ![]() |
Thank you for your advice. I apply 3 mm as based grid size when I use RANS model. How much should I decrease order of based grid size, when I use LES model.
Best regards |
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#4 |
New Member
Alireza Mashayekh
Join Date: Aug 2017
Location: Convergent Science, Madison WI
Posts: 14
Rep Power: 9 ![]() |
We have not done a grid convergence study for LES models in engine simulations. We know that for sprays, LES models converge around 62.5 um, but using such a fine mesh in an engine would make the simulation very expensive.
So, it is up to you to run some cases and see at what grid size you get proper results. Best, |
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#5 |
New Member
kazuki
Join Date: Jan 2017
Posts: 5
Rep Power: 9 ![]() |
I appreciate your comment. I'll try to do that.
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Tags |
converge cfd, diesel engine, les |
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