I made a simple simulation of an airfoil just to investigate if I could get a good Y-plus value after reading this post.
- Airfoil with 1 meter chord length
- Background mesh box = 7x3x3 m
- Turbulence model = k-omega SST
- Free stream velocity =1 m/s
Calculation of first layer thickness
I used this site: http://www.pointwise.com/yplus/, to calculate the wall spacing.
Here is what I put in to the calculator:
So the first layer should be 0.00029 m.
If I have 6 inflate boundary layers and an expansion ratio of 1.4, this gives me the following final layer thickness:
and the total thickness of the inflate boundary layers would be 0.00029*1.4^0+0.00029*1.4^1+0.00029*1.4^2+0.00029*1.4^3+
The overall thickness from the meslog seems th correspond well with the calculated value:
So after I made the simulation I imported the result into paraview. This is how it looks:
As you can see, the Y-plus seems to be below 0.05 for most of the wings surface. Is it normal to have so big difference between the estimated value and the actual value?