Hi

I read 2 paper about unsteady supersonic flow.

1- Morino, Luigi. "A general theory of unsteady compressible potential aerodynamics." (1974).

2- Garrick, Isadore Edward, and S. I. Rubinow. Theoretical study of air forces on an oscillating or steady thin wing in a supersonic main stream.

Morino used nonlinear unsteady compressible potential flow and Green function. Then he made some assumption such as small perturbation and eliminated nonlinear term on RHS. (see pages 39 & 45 for final formula)

In other hand, Carrick used linearized unsteady potential flow and fundamental solution (which is based on Green function) and made his method.

both of these methods are based on small perturbation and Green function, but Morino has a second term which is not in Carrick's work. Albeit Morino said for symmetric supersonic edges, his formula is in agreement with Carrick's formula.

It means that, Morino's work is more general than Carrick.

Now my question is, both of them have same assumptions and method. What is difference in their works?

I think, there is difference in their methods which I have not noticed it.

Anyone has experience in this topic to clear difference between this two methods?

Thank You