[TurbJet]

Hi,

According to J.D.Anderson, Fundamentals of aerodynamics (2017), it is the nonlinear velocity potential equation can be (and should be) applied to both transonic/hypersonic flows, whereas we can apply a simpler version -- linearized potential equation to supersonic flow.

I can't wrap my mind around this. I can understand hypersonic flow having strong nonlinearity, but why supersonic doesn't? And wireder, why transonic is highly nonlinear? (and this makes me remember that I read somebody said that transonic flow is harder to solve than supersonic due to strong nonlinearity)

I mean, based on the flow regime, supersonic "sits" between transonic and hypersonic. Intuitively, if transonic/hypersonic flow is highly nonlinear, supersonic should be as well. But the theory says the other way.

So why? Can anyone explain this?

Thanks.