boundary conditions
 

hi,

I KNOW FLOW RATE and PRESSURE DROP(BETWEEN INLET AND OUTLET) Which B.Cs. should i select. the problem is of pipe flow with one inlet and one outlet.

Thanks in advance

Re: boundary conditions
 

There's a relation ship between the flow rate and the pressure drop, so i think that in both way you should have the same results! the easiest way i think that's to use the pressure boundries for both inlet and outlet of the pipe.

Re: boundary conditions
 

Both are fine and should give you same results upon convergence. But fixed mass flow rate will normally converge faster.