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-   -   Y+ quick question...probably pretty easy. (https://www.cfd-online.com/Forums/ansys/101645-y-quick-question-probably-pretty-easy.html)

 eishinsnsayshin May 9, 2012 17:30

Y+ quick question...probably pretty easy.

Hey all,
Just wondering, when I look at a 3d FLUENT simulation results, and I look at contours on a wall surface of Wall Y+...what is that based off of? My understanding is that the "y" value in the y+ equation is based off of the distance from the wall...so when you look at contours of Y+ on the wall itself, are these based off of the 1st node off the surface? If so, is there a source that says this? I can't find it in the fluent user guide.

Thanks in advance for any replies!

 Far May 11, 2012 05:01

you are correct partially. There are others parameters are there to calculate the Y+.

 LuckyTran May 14, 2012 01:19

Quote:
 Originally Posted by eishinsnsayshin (Post 360173) Hey all, Just wondering, when I look at a 3d FLUENT simulation results, and I look at contours on a wall surface of Wall Y+...what is that based off of? My understanding is that the "y" value in the y+ equation is based off of the distance from the wall...so when you look at contours of Y+ on the wall itself, are these based off of the 1st node off the surface? If so, is there a source that says this? I can't find it in the fluent user guide. Thanks in advance for any replies!
you are exactly correct about y and y+. When you plot "Wall Y+", you are plotting the y+ of the 1st closest grid point to the wall. Also note that when calculating y+, the distance to the NEAREST wall is used for the y. The distance to the nearest wall is calculated using the distance formula.

 eishinsnsayshin May 14, 2012 20:13