Experimental study on the vortex tubes with different Mach number nozzles

In order to find out the vortex tube configuration with the best cooling temperature difference,nozzles with different Mach numbers were designed and manufactured,the experimental system was set up and the performances of these nozzles were measured.The result shows that the vortex tube has better energy separation effect with outlet Mach number between 0.5 and 0.8.But when the Mach number is up to 0.9,the effect would be worse.The refrigeration performance of the vortex tube with the outlet Mach number of 0.8 is best from 0.4 to 0.6MPa in inlet pressure,but the performance difference varied little with input pressure over 0.6MPa.