I am looking at placing an impingem

[Bill3752]

I am looking at placing an impingement plate on the end of a 5' diameter stack. We are looking at placing it 10' (two pipe diameters) above the stack. I am interested in whether there may be enough back flow off of the plate that might cause a flow disturbance in the stack itself. We are doing some environmental stack testing and are looking for a low flow discontinuity.
I am not sure what math to go through to evaluate.

 

[georgeverghese]

The last time I went through these vent dispersion simulation programs ( PHAST, Shell's proprietory FRED, probably many others ), there were no options to include things like divertor plates or conical rain hats on these vents, but this was some 10years ago. Maybe some one has more recent information on these simulators.