Hi Barry, Just want to get clarification on what you mean by ‘optimal values’, I think maybe it’s best if I explain what the parameters mean?
if so here is a brief explanation:
the number of layers = n: the number of layers you want to inflate, if you have very large cells at the boundary but the desired y value is very small in comparison then you might want to inflate slowly over many layers.
Expansion ratio = R: the rate in which the layer will increase, for example, if the first layer is 1mm thick the second will be 1.3mm and so on and so forth.
The thickness of final layer = Y_final: the thickness of the last inflated layer, this will be Y_first*R^n = Y_final. Y_first being based upon the desired 1st y+ distance, if modelling as a wall function this will be 30<Y+<200 and there is a calculator on CFD online to calculate y based on Y+.
[-] or [m] is weather or not relative or absolute values are being used in the main mesh settings (use absolute if you need a particular distance)
And for the bounding box layer addition, you need to choose which face you will be inflating.
So there isn’t really an optimal set up of such, it really does depend upon your case, the flow and many other things.
Let me know if you need more info on anything in particular?
Best regards,
Darren