Experimental Investigation Of Energy Separation Process In Vortex Tube

The Ranque-Hilsch Tube was discovered in 1930 by French Physicist, George Ranque. The mechanism behind the tube lies in the swirling flow of the air with the tube. As a simple device without moving parts, vortex tube is composed of nozzle, vortex chamber, separating plate, control valve, hot-end and cold-end. In the swirl, air stream at the periphery tend to have higher temperature compared to that in the center. By means of a separating plate, the airflow is separated into streams of hot and cold air. Each stream of air then emerges from a particular end of the tube, named the cold and hot end accordingly. The objective of this project is to conduct an external study on the energy separation of the tube by varying various parameters, like inlet temperature, backpressure, tube length and nozzle of the tube.An experimental set-up that includes experimental apparatuses and measuring system is constructed. Relative ways for decreasing experimental inaccuracy are offered.Experiments have been taken under the conditions of inlet pressure from 0.25MPa to O.TOMPa, inlet temperature from 12癈 to 32癈, and the mass volume flow from Om3/h to 30m3/h. Some valuable results have been obtained through a large quantity of experiments as follows.The inlet temperature of the air has certain influence on the energy separation of vortex tube. The performance of refrigerating increases while the performance of heating decreases with the rising of inlet temperature on the condition of inlet pressure from 0.25MPa to 0.70MPa.It is offered firstly that the backpressure has great influence on energy separation. This is an effective method for adjusting the performance target of vortex tube.inCold gas fraction is one of the most important parameters at influencing the performance of vortex tube. Adjusting the cold gas fraction can control the performance target of vortex tube with fixed other parameters, which offers some referring data for practice applications of vortex tube.The inlet pressure is one of the important factors for influencing the performance of vortex tube. The separation of hot and cold is not very obvious at Pj=0.20MPa. The separation of hot and cold is very obvious from Pj=0.25MPa to Pi=0.60MPa with the rising of inlet pressure. The tendency of the increase of energy separation decreases after the inlet pressure beyond 0.60MPa.The configuration of the nozzle has great influence on the performance target of vortex tube. Three kinds of nozzles have been measured in our experiments.Some considerations of the further study on vortex tube are proposed and the application prospect of vortex tube is analysed.