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Yacine November 23, 2003 15:03

temperature over shoot
 
Dear all; I am running an LES calculation in a case with bouancy effects. The problem is I am supposed to get temperatures between 42 an 34 within the domain but I get some over shootings in some regions of the domain any one knows if it is possible to use clipping in STAR to limit the temperature to the min and max values? either by using a user soubroutine or some parameter I don't know about in the code ? S.P: I am using CD scheme for the convection which should be the optimum for LES runs. Thanks

Ossi November 24, 2003 02:51

Re: temperature over shoot
 
Try the GAMMA scheme for the temperature with a blending factor of bf=0.5. The GAMMA scheme should be among the best choices for discretization. On the other hand, it is more time consuming than the other schemes. For my applications, the GAMMA scheme for temperature reduced the maximum gas temperatures.

Yacine November 25, 2003 08:44

Re: temperature over shoot
 
I am not sure how dessipative is the gamma scheme so I'll need to run THI to find that out ! I got a reply from the developpers and there is a solution for the clippings: You can limit temperature by switching on switch 159 and setting rcons 142 - lower limit rcons 143 - upper limit THis information may help some one who is having the same problems thanks



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