# Glider CFD Project

**URL:** <https://www.simscale.com/forum/t/glider-cfd-project/86644>\
**Category:** Project Support\
**Created:** [October 22, 2019, 2:01pm UTC](https://www.simscale.com/forum/t/glider-cfd-project/86644 "2019-10-22T14:01:19Z")\
**Posts on this page:** 1\
**Showing post:** 10

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**Author:** ![Ricardopg](https://www.simscale.com/forum/user_avatar/www.simscale.com/ricardopg/32/26909_2.png) [@Ricardopg](https://www.simscale.com/forum/u/Ricardopg)\
**Post date:** [October 23, 2019, 1:15pm UTC](https://www.simscale.com/forum/t/glider-cfd-project/86644/10 "2019-10-23T13:15:44Z")

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Hey Taichi,

There are a bunch of y+ calculators online, like [this one from cfd-online](https://www.cfd-online.com/Tools/yplus.php) or [this google spreadsheet](https://docs.google.com/spreadsheets/d/14pyIX1fa2QN4fRC72gJ7UXn8PYTL76Al/edit#gid=498900685). These are reliable but I do recommend that you make your own spreadsheet for y+ evaluation.

So basically these calculators take a desired y+ as input and return the thickness of the first cell. It gets a little bit tricky here though, because a lot of solvers, SimScale included, calculate the solution at the cell centroid. So you should multiply the calculated first cell thickness by 2 before taking it to SimScale.  
Just to give an example, let’s say the calculator returned a value of 0,002 meters for the first layer thickness, If you input this value to SimScale, the solver is going to calculate the solution at the cell centroid (0,002/2 = 0,001 meters) which will result in a y+ that is too low. By multiplying 0,002 meters by the factor of 2, your first cell centroid will be correctly placed at the desired 0,002 meters mark.

 ![image](https://www.simscale.com/forum/uploads/default/original/3X/c/1/c19a7e895fa847a3156e7ce8d04b1b2a4933f7c4.png)

Hopefully I could get my point across 😅

/Ric

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