Experiments were carried out to study the influences of the inlet/outlet expansion ratio (2~5)

the throttle setting value (1~11) and the inlet temperature (313~373K) on vortex tubes performance. The variation of refrigeration and heating effects was obtained along with above parameters. It was found in experiments that the performance of vortex tube was enhanced with the increasing inlet expansion ratio

promoting the in-tube vortex intensity and increasing inlet the angular velocity gradient at different radiuses. The refrigeration effect increased by 10.9% and heating effect increased by 46.5% separately. With the rise of throttle setting value

the degree of energy exchange between the cold/heating flow increased

the eddy effect strengthened and cold flow rate increased by 47.3%. The performance of the vortex tube was improved with the increase of the inlet temperature. All the results show that as the inlet temperature increases by every 20K

the refrigeration effect at the cold side is enhanced by about 12%

while the heating effect at hot side is improved by about 5%.