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Model Switch, RANS to LES?

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Old   July 7, 2015, 11:30
Default Model Switch, RANS to LES?
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I am running a spray simulation and was reading a paper recently by C J Rutland called "Large-eddy simulations for internal combustion engines - a review"

The following passage about RANS to LES simulations leads me to believe that one should not simply run a RANS simulation and then if all goes well, re-run it on LES which would involve only changing the turbulence model and SGS submodel for LES. (Obviously, grid requirements would have be addressed)

The passage reads:
Models (sometimes called submodels) are required, not only for turbulence, but also for liquid sprays, combustion, and various scalar processes. This means that LES modelling for engines should be more than just using a turbulence model, such as the dynamic Smagorinsky model, and leaving all of the other submodels the same as RANS models. Unfortunately, this approach is fairly common.... Proper use of LES in engines requires potential modification of many submodels to make them consistent within the LES context.
My problem is that I cannot think of anything I would change about my simulation other than changing RANS and its submodel to LES and its submodel (AKA his idea of the "unfortunate, common approach". The gas phases have an Eulerian representation and the liquid injection is represented by a Lagrangian phase and appropriate physics models.

If anyone knows what is meant by that quote in terms of changes aside from turbulence models, please share your insight
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