engleski

Numerical and Experimental Analysis of Counterflow Vortex Tube

The vortex (Hilsch, Ranque) tube is a simple appliance in which a thermal separation of the gas flow occurs, resulting with two streams, one of which is colder and the other hotter than the incoming one. The phenomenon is yet not entirely physically explained. The paper offers an analysis of the flow and thermal process in a counter-flow low-pressure vortex tube. The analysis is done using the FLUENT software package. The calculation of compressible laminar and compressible turbulent flow is performed where, for the latter, the standard k-e model of turbulence for high turbulent Reynolds numbers is applied. For the laminar model flow, the "no slip" boundary condition is applied at the tube surface, and for the fluid viscosity, the average value obtained for turbulent flow is taken. The obtained data are compared with experiments performed for this purpose. An explanation of the obtained results is given in the light of published theories on the thermal separation in vortex tubes. Thermal separation is also recorded at laminar flow conditions, indicating that turbulence is not the only reason for it. The calculation results are in qualitative accordance with the experiment, but quantitatively they forecast somewhat lower thermal separation effects, which may be reduced to the turbulence model applied.

vortex tube; numerical analysis; experimental analysis

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