LAUSR

Abstract As an interesting thermal device, the vortex tube (VT) uses the instantaneous expansion process of compressed gas to provide the conditions for cooling and heating usages. At the beginning of the entry into the vortex chamber, the compressed gas is forced to be guided in the pipe path by a piece named the navigator. This piece has a small angle to guide the gas longitudinally, and this angle has a very important effect on the efficiency of the VT. This research investigates the impact of the navigator angle (0–15 deg) on the energy separation and the internal gas velocity variations (swirl and axial). The results show that the navigator angle of 10 deg creates the highest cooling and heating capabilities as well as the highest values for the axial velocity and also for the swirl velocity drop. When the angle increases from 10 deg to 15 deg, the cold temperature difference changes from 22.32 K to 17.37 K, which indicates 22.19% decrease in the temperature difference. Also, increase in the angle from 0 deg to 5 deg leads to 4.28% and 5 deg to 10 deg leads to 1.2% improvement in the hot temperature difference. The results of the velocity measurements inside the VT are compared and confirmed by other valid researches.