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.

1. Geometry of the problem

2. Velocity profiles

3. Pressure contours

4. Density contours

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