A computational fluid dynamics (CFD) investigation has been conducted to realize the effect of convergent nozzles on the cooling capacity enhancement of vortex tube. The CFD models have involved turbulent, compressible and axisymmetric swirling flow utilizing the standard k-ε turbulence model. The studied vortex tube has been equipped with the six convergent nozzles. Convergence angle of applied nozzles showed a significant role in achieving to the highest degree of refrigeration, such that the maximum possible amount of cold temperature difference is provided at the angle of 8° (degree respect to nozzle entrance). Therefore, to be presented numerical results include of performance curves, temperature separation rate and particularly swirling flow angular velocity as an important criterion represent a reasonable justification. Finally, obtained results particularly temperature differences are compared with some of the available experimental data which show good agreement.
vortex tube, divergent nozzles, numerical simulation, temperature separation
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