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Sachin November 3, 2008 08:21

yplus at high Re
 
I am dealing with a high pressure(250 bar, 600-800K temp) supercritical water flow through a channel. i want to know, what will be the range of y plus at Re(50000 to 70000). thanks

John S. November 3, 2008 14:05

Re: yplus at high Re
 
Y+ is grid dependent.

sachin November 3, 2008 15:01

Re: yplus at high Re
 
in my case, mesh is corse with boundary layers not much refinement at the wall. using k-epsilon model with scalable wall functions. after postprocessing the results i got yplus in the range of 2000 to 2500. i dont know it is correct or not. local Re is in the range of 50000 to 70000

Glenn Horrocks November 3, 2008 17:42

Re: yplus at high Re
 
Hi,

Do a mesh sensitivity check to determine if this y+ value is OK.

Glenn Horrocks

sachin November 4, 2008 07:39

Re: yplus at high Re
 
thanks glenn and john

pratik mehta November 11, 2008 10:44

Re: yplus at high Re
 
I think you really need to make hybrid mesh . It seems from your values of Y plus, you don`t have one, any ways try to get a bit closer to the wall, determine your first cell height some iterative procedure,

I am sure you will get good results


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