Effect of Conical Valve Angle on Cold-Exit Temperature of Vortex Tube

Abstract

The control valve is a part of the vortex tube system, which controls the flow fraction at the hot end of the main tube. In the present experimental study, the parameters are focused on some geometrical and operational parameters such as conical valve angle, inlet pressure, and number of nozzles. The effect of the conical valve angle variation has been analyzed in the range of 20 to 80 deg. A computational fluid dynamics model was employed to predict the pattern of the airflow and heat transfer inside the vortex tube. The numerical investigation was done by full three-dimensional steady-state computational fluid dynamics simulation using FLUENT6.3.26. This model uses the Reynolds stress model to solve nonlinear flow equations. Experiments were also conducted to validate results obtained for numerical conclusions. Experimental and numerical results show that the best candidate for optimal cone angle is , which creates a cold temperature difference equal to 27.98 K and 27.45 K, respectively. The first purpose of numerical study in this case was validation with experimental results to confirm these conclusions, and the second was optimization of the experimental model to achieve the highest efficiency.