I have a piece of ducting with one inlet and two outlets, that has high pressure, high temperature air flowing through it (at a maximum of about Mach 0.3 to 0.5).

I know the inlet pressure and mass flow rate. However, I have only been given the outlet mass flow rate and not pressure.

I have mass-flow-inlet for the inlet, and a pressure-outlet at the exit. I need to set the pressure on the exit, but do not have any information, has anyone had experience with this?

I cannot use the outlet boundary condition because it is compressible flow.

Thank you

Andrew

Hi Andrew,

If you have been given the mass flow for both outlets separately, use the feature "target mass flow rate" at your pressure outlet conditions. If you specify this quantity, fluent will adjust the pressure at the outlet iteratively until the target mass flow is reached. To speed up your convergence, the initial guess of pressures at outlets should be as good as possible. I would also recommend to use pressure inlet rather than mass flow inlet.

Max