TY - JOUR
TI - Numerical investigation of operating pressure effects on the performance of a vortex tube
AU - Pourmahmoud Nader
AU - Zadeh Amir Hassan
AU - Moutaby Omid
AU - Bramo Abdol Reza
JN - Thermal Science
PY - 2014
VL - 18
IS - 2
SP - 507
EP - 520
PT - Article
AB - A three-dimensional computational fluid dynamics simulation of a vortex tube  has been carried out to realize the effects of operating pressure. The highly  rotating flow field structure and its characteristic are simulated and  analyzed with respect to various operating inlet pressure ranges. Numerical  results of compressible and turbulent flows are derived by using of the  standard k-ε turbulence model, where throughout the vortex tube was taken as  a computational domain. The main object of the present research is to focus  on the importance of identifying the suitable inlet gas pressure corresponds  to used vortex tube geometry. Achieving a highly swirling flow and  consequently maximum cold temperature difference were the key parameters of  judgment. The results revealed that these acceptable conditions of machine  performance can be provided when the inlet operating pressure is appropriate  both to mechanical structure of machine and physical properties of working  fluid. The stagnation point location in the axial distance of vortex tube and  Mach number contours in the vortex chamber as additional information are  extracted from flow filed; such that interpretation of shock wave formation  regions may be accounted as significant features of investigation. Finally,  some results of the CFD models are validated by the available experimental  data and shown reasonable agreement, and other ones are compared  qualitatively.