Learning Forum

[devaverma]

My question is regarding how we set the maximum height of inflation layer? what are the calculations for it?

1) In turbulent flow if my y+ < 1 , how much number of layers of inflation should I give and how do we set the total height of inflation layer.

2) If we set 5>Y+<10 then how should we set the maximum height of inflation layer.

3) If we set 30>Y+<50 then how should we set the maximum height of inflation layer.

[Rob]

If you read the theory how deep is the boundary layer?  

[devaverma]

up to 0.99 velocity right ? 

[Rob]

Pass, I usually add inflation to suit what I think is going on and then remesh or adapt if I need more cells in a region.

[devaverma]

Thank you.  As said is there any method to increase or decrease the total inflation height after taking initial results of any flow variables ? what are these variables and how do we read it? is there any material available on this in internet?

[Rob]

You'd need to remesh and probably use the "total" height option. Drawback is then you may not hit the near wall cell requirements. All the inflation options are covered in the manual(s) that come with the software, click "help" to access these. 

[devaverma]

I know how to give in software but my question is theoretically up to what height we should give inflation

[Rob]

Far enough to resolve the near wall flow. Inflation is available so you can stretch the near wall cells to keep the cell count at a manageable level: you can mesh without it but that (usually) gives very high cell counts.