The phenomenon of noticeable temperature distribution in confined steady rotating gas flows is referred as Ranque-Hilsch Effect. The simple counter-flow Ranque-Hilsch tube consists of a long hollow cylinder with tangential nozzle at one end for injecting compressed gas. Rotating gas escapes the tube through two outlets - a central orifice diaphragm placed near the injection nozzle plane (cold stream) and a ring-shaped peripheral outlet at the opposite end of the tube (hot stream). The flow is essentially three-dimensional, turbulent, compressible, and spinning; such that any theoretical simplifications are questionable, if at all possible. The area of practical vortex tube applications is wide - ranging from local cooling industrial devices to mixture and separation equipment.. The results of our research on vortex tube were reported by Vlad Bezprozvannykh and Hank Mottl at 11th Annual Conference of CFD Society of Canada (2003, Vancouver, British Columbia), and got numerous responses from readers from all over the world.