Setting up static pressure inlet boundary condition in Ansys Fluent for internal flows
Many times static pressure information is the only information available for internal flow problems. However, the pressure inlet boundary asks for input of the total pressure (rather than static pressure) that also includes the dynamic pressure term. In such a situation, it is suggested to use a series of CFD runs with a assumed inlet mass flow rate and a known outlet static pressure as boundary conditions. At the end of each run, user may calculate the mass-weighted average of inlet static pressure. If the calculated value is higher than the target inlet static pressure, the inlet mass flow rate should be reduced, and if the calculated value is lower than the target inlet static pressure, the inlet mass flow rate should be increased. Once the target static pressure at the inlet is achieved, the model solution has been obtained.