Experimental investigation on energy separation in a counter-flow Ranque–Hilsch vortex tube: Effect of cooling a hot tube

This paper presents the effects of cooling of a hot tube on the temperature separation (the temperature reduction of cold air) and cooling efficiency in a counter-flow Ranque–Hilsch vortex tube (RHVT). In the experiments, the hot tube is directly cooled by cooling water jacket. The obtained results reveal that cooling water plays an important role in promoting the energy separation in the RHVT. Consequently, the temperature reduction of the cold tube (Ti − Tc) and thus cooling efficiency in the RHVT with cooling of a hot tube is found to be higher than those of the RHVT without the cooling, under the similar operating conditions. Over the range investigated, the mean cold air temperature reduction and cooling efficiency of the RHVT with the cooling of a hot tube are respectively, 5.5 to 8.8% and 4.7 to 9% higher than those of the RHVT without the cooling.