Numerical simulation of different turbulence models aiming at predicting the flow and temperature separation in a Ranque-Hilsch vortex tube

Abstract

A computational fluid dynamics model is used to compare the effect of different Reynolds averaged Navier-Stokes based turbulence models in predicting the temperature separation and power separation in a Ranque-Hilsch vortex tube. Three first order turbulence models (standard k-ε, renormalized group and shear stress transport k-ω model) together with a second order numerical scheme are surveyed in the present work. The simulations are done in 2-D steady, axisymetric with high swirl flow model. The performance curves (hot and cold outlet temperatures and power separation vs. hot outlet mass fraction) obtained by using these turbulence models are compared with the experimental results in different cold mass fractions. The aim is to select an appropriate turbulence model for the simulation of the flow phenomena. Because of large discrepancy between 2-D and experiment, validation in 3-D model is also considered. The performance analysis shows that among all the turbulence models investigated in this study, temperature separation predicted by the renormalized group model is closer to the experimental results.