A supersonic corner: Mach 2.00 turning 10° away from itself

The fan is a continuum of Mach waves and the flow is turned by an infinitesimal amount across each one, so nothing about the process is abrupt. The leading wave sits at the Mach angle of the flow arriving; the trailing wave sits further back, because the flow leaving is faster and its Mach angle is smaller. The fan opens, which is exactly why it cannot concentrate into a shock.

3 essays call expansion-fan. The drawing above is what it returns with no arguments at all; every call below passes it something, because a placement that passes nothing draws whichever member of the family the generator happens to default to rather than the one its essay argues about.

It is also the blast radius. Changing expansion-fan changes every figure listed here at once, and on this site it may change what they assert as well as what they show — which is what has to be rebuilt and looked at before the change is believed.