Mass flow boundary conditions for subsonic inflow and outflow boundary

The development and verification of an inflow and outflow mass flow boundary condition are described. In addition, an outflow Mach number boundary condition was implemented and tested.The main motivation behind the development of a mass How boundary condition is a need to bridge the gap between the requirement of direct setting of mass flow as one of the most important parameters, and the difficulty of indirect control of mass flow using static pressure outflow and total states inflow boundary conditions. The mass flow and Mach number boundary conditions were verified in low-speed flow through a two-dimensional channel with constant area and in high-speed flow through the Royal Airforce Establishment M2129 S-duct with large separation. Special attention was paid to the behavior or the mass flow boundary conditions in choked flow.