Computational analysis for temperature separation and correlations prediction for dual-inlet-sections vortex tube.

This article intends to examine the cooling capacity enhancement for the Ranque-Hilsch vortex tube when two inlet sections are introduced compared to a single inlet section along with the optimum distance between the intake sections by computational fluid dynamics (CFD) approach. Air is taken as working fluid in a steady-state, 3-D, axisymmetric, Ranque-Hilsch vortex tube. ANSYS FLUENT software has been used to simulate flow using standard k-ɛ turbulent model. The numerical analysis is accomplished with variable intake pressure and validated with the experimental results. The numerical investigation shows that using the two inlet sections decreases the fluid temperature at the cold outlet as compared to single inlet section, but the cold and hot exit fluid temperature increases by increasing the distance between the two sections. The optimum cold outlet temperature value occurs at a dimensionless distance between intake sections of ζ/L = 0.075 and a temperature difference of 19.27 K at cold exit between single and double inlet section of vortex tube has been found from the present study. A correlation has been developed for the hot temperature gradient (ΔTh) and cold temperature gradient (ΔTc) by considering the operating parameters such as mass fraction and inlet pressure. [ABSTRACT FROM AUTHOR]