Below you can see visualization of aerodynamical transient process in Ranque-Hilsch Tube with quadratic cross-section . Starting conditions are: - constant temperature; - linear 'roof' pressure distribution; - quasi-solid flow rotation in the tube. Time axis: - 1042 steps ; - start : 0.000000 s; - end : 3.520e-3 s. Seed source line at x= 0.15 m (from hot exit) and y=0, z=0.