Freinds I have solved a combustion problem using non premixed combustion model in Fluent. Am getting every thing correct but, getting a high value of wall y-plus,...

can any one tell me how to reduce wall Y-Plus,...

waiting for u'r reply,...

regards,.....

rams

Go to Adapt - Yplus/Ystar panel... Turn on Refine option, select wall zones yoe wih to refine, set the min and max allowed values of Yplus, and click Adapt ...

Hi!

The adapt option is ok, BUT: most of the time, it can only dubble or half the y+ values, because the position of the nodes can not be changed with that option. So changing of yplus means to add or remove a node, and the addition can only happend in the middle of a cell.

One hint: Use the smooth/swap option after adapting yplus, do some iterations until convergens, than do the yplus adaption again.

Much better is it, to build a grid with the right yplus from the beginning. Use sizing function and/or Boundary layer option in gambit.

To estimate yplus, have a look at: http://www.cfd-online.com/Forum/main...cgi?read=44320

Ralf

I would build a grid imposing the yplus that I wanted, and then recalculating the cell size. As I know you need to estimate velocity of the adjacent flow, carachterist length of the problem, Cf and Ue.