Hydraulic flow instability in a Ranque tube

The flow in a Ranque tube with a square cross-section channel was studied within the framework of the hydraulic concept of strongly swirling flow with a circulation zone. Using experimental data, it has been found that the flow in the vortex tube satisfies the hydraulic condition of flow crisis: the longitudinal speed becomes equal to the speed of propagation of centrifugal waves at the boundary between the vortex and the circulation zones. It is shown that the temperature change along the flow occurs mainly in the region of the working channel in which the ratio of the longitudinal velocity at the vortex boundary to the propagation velocity of centrifugal waves fluctuates about unity assumption made The existence of a previously unknown mechanism of energy separation due to the presence of hydraulic jumps during the development of internal waves in a Ranque pipe was assumed.