BY : CHAM Consultancy Team

The flow considered is supersonic flow through a cascade of wedges with inlet Mach number 3.0 and completely supersonic flow.
A leading-edge shock reflects off the pressure surface and should be exactly cancelled at the upstream corner giving a uniform parallel flow through the two surfaces. The flow then expands off the downstream corner and exits through the blade row where two compression waves are formed at the trailing edge.
Cyclic boundary conditions are applied upstream and downstream of the cascade.
For simplicity, the flow is treated as isentropic. However, shock theory indicates that there is a significant entropy change across the shocks for the given approach Mach number and wedge angle. Therefore, in other work the isentropic treatment may be replaced with one which allows for entropy changes across shock fronts.
The exit boundary condition is one of fixed pressure according to the post-expansion pressure calculated from gas-dynamic theory; this neglects the presence of trailing-edge shocks.
The system of units used is such that the pressure, temperature and density are defined in terms of the ratio to the inlet conditions, while the velocity is in terms of the Mach number.

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