Numerical energy separation analysis on the commercial Ranque-Hilsch vortex tube on basis ofapplication of di erent gases

In this numerical study, energy separation analysis of a Ranque-Hilsch Vortex Tube (RHVT) has been investigated for dierent conditions such as operation of machine under applying dierent inlet gases. The utilized gases in this study are nitrogen dioxide (NO2), carbon dioxide (CO2), oxygen (O2), nitrogen (N2) and air. The cooling and heating performance in a commercial vortex tube for the mentioned gases has been described in details and illustrated by dierent curves. The present three-dimensional (3D) Computational Fluid Dynamic (CFD) model is a steady axisymmetric model that employs standard k-" turbulence model to perform the computational procedure of results. Various key parameters including cold and hot exit temperature dierences and energy separation rates are described numerically. The results show that NO2 enhances the greatest amount of cooling and heating capacity among investigated gases. Some of the numerical results are validated by available experimental data. Furthermore, a comprehensive comparison is performed in this article between two dierent kinds of boundary conditions for cold and hot exhausts, i.e. pressure-outlet and pressure-far-eld.