Supersonic Flows
Supersonic flow through a jet engine
FLOW-3D has a powerful compressible flow capability across a variety of Aerospace applications, including suspersonic flows. Here
is an example of supersonic (Mach 3.1) flow through a jet engine with a spike.
The gas is air. The engine is about 5 meters long and 1.5 meters in diameter.
The spike is designed to optimize the flow of air in the intake by moving forward
and backward as the plane's speed and the upstream flow conditions change (similar
to a Blackbird spy plane engine). Ideally, the spike should be positioned so
that the primary shock wave originating at its nose impinges exactly on the leading
edge of the intake nozzle.
The spike is not positioned optimally in the simulation, therefore, the shock wave is located inside the engine, about 20 cm from its leading edge. Multiple reflections of the primary shock inside the engine create secondary waves, as can be seen in the insert. Heat is added to the air near the downstream end of the spike to simulate the burning fuel.