Numerical investigation on flow behavior and energy separation in a micro-scale vortex tube

Abstract

There are a few experimental and numerical studies on the behavior of microscale vortex tubes. The intention of this work is to investigate the energy separation phenomenon in a micro-scale vortex tube by using the computational fluid dynamic. The flow is assumed as steady, turbulent, compressible ideal gas, and the shear-stress transport k-ω is used for modeling of turbulence phenomenon. The results show that 3-D computational fluid dynamic simulation is more accurate than 2-D axisymmetric one. Moreover, optimum cold-mass ratios to maximize the refrigeration-power and isentropic-efficiency are evaluated. The results of static temperature, velocity magnitude, and pressure distributions show that the temperature-separation in the micro-scale vortex tube is a function of kinetic- -energy variation and air-expansion in the radial direction.