mdunphy / djles Goto Github PK

I am wondering why the flow velocity at x→0 and x→L are nearly zero In the moving reference, is that implies, that in the rest frame the flow velocity away from the wave is uniformly u=c(c is the wave speed)?

For example. the picture below showed the flow field of "case-small-ape" of DJLES

From the picture we can see when |x-2|>0.5, both u and v are nearly zero. I have checked the data table and am sure about this. Now I want to study the ISW in the rest frame, so it seems that I have to perform u(rest frame) = u(moving frame) + c, which lead to a seemingly strange flow field.

And a strange result is, if I place a particle ahead of the ISW, it would be carried away by the uniform flow "u=c" and it would be never affected by the ISW.

I am new to ISW but I have read lots of articles since encountered this problem, and it is still puzzling me after several weeks. I would be grateful if someone can help me out :)