Which boundary condition is better? Please help.
 

Hi,

I ask this question in CFX forum but no one is able to give an answer. I hope anyone here can at least tell me whether "the inlet total pressure-outlet static pressure BC pair is sensitive to the initial guess while inlet velocity-outlet static pressure BC pair is not" is true and why.

I'm asking this because I need to use the inlet total pressure-outlet static pressure condition for transient simulation but I use the other setting for steady-state simulation.

I get this idea in the CFX user manual but still not able to find any detailed explanation about it.

Thank you very much for your help. Sam

Re: Which boundary condition is better? Please hel
 

This will depend on how the boundary conditions are implemented. Let's get some more info first: Total pressure or inlet velocity cannot be the only parameters specified at the inlet. What other parameters are used at the inlet: total temperature, enthalpy, entropy, flow direction... ?