How to determine number of prism layers and total height

ekraft · July 12, 2016, 16:15

Like the title says, how do you know how many prism layers to use and total height of the prism layers? I was able to calculate my near wall length in order to get my y+ value to be less than 1 at the wall, but I'm not sure how to determine the total length. Attached are two images of my inlet face and a zoomed in picture of a prism layer transition. The cells of the last prism layer are much smaller than the first layer of tetras. Is that concerning? Thank you!

LuckyTran · July 13, 2016, 02:33

After you have satisfied your first cell height to achieve whatever y+ criteria you need, choose as small a growth ratio that you can afford.

Then, you want a smooth and gradual transition between cell sizes. So choose the number of layers and total thickness such that the last prism layer is ~ the same size as the first tet.

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July 13, 2016, 02:33		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,704 Rep Power: 66	After you have satisfied your first cell height to achieve whatever y+ criteria you need, choose as small a growth ratio that you can afford. Then, you want a smooth and gradual transition between cell sizes. So choose the number of layers and total thickness such that the last prism layer is ~ the same size as the first tet.