difference in results...

mateus

Hi,

I'm simulating flow in an open valve (it's almost only a pipe). First I did a simulation with mass flow inlet and pressure outlet bc. When I checked the results the pressure difference upstream and downstream of the valve was about 30% too high. In the second simulation I set the pressure inlet and pressure outlet bc and checked the flow rate. This time the results were correct. If I repeat the simulation giving the last flow rate as a bc and check the pressure difference the result is again wrong.

Has anyone encountered something like that...such a influence of the (in essence the same) boundary conditions?

Thanks for the answers Mateus