Experimental and 3D CFD investigation on energyseparation inside a convergent vortex tube air separator

Abstract. The vortex tube air separator is an invaluable tool which has the ability to separate a high-pressure uid into the cold and hot uid streams. The hot tube is the main part of the vortex tube, along which the energy separation procedure happens. This research has been done to analyze the eect of the convergent angle and cold orice diameter on thermal eciency of a convergent vortex tube. The convergent hot tube angle varies over the range of 1 to 9 deg. Attention to the main angle eect denotes that the highest thermal ability could be achieved at  = 5 deg. Experiments denote that both cooling capability and heating eectiveness reach the highest magnitudes when DCold is around 9 mm. After these two stages, the optimized convergent vortex tube is capable of decreasing and rising air temperatures at the cold and the hot sides up to 9.05 K (42.89%) and 10.48 K (44.74%), respectively. A computational uid dynamics model is employed to predict the performance of the convergent vortex tube. The numerical investigation is done by full 3D steady-state CFD-simulation using FLUENT6.3.26. The results show that the agreement between computation predictions and laboratory measurements is fairly good.