喷嘴喉部与涡流室面积比对涡流管性能的影响OA

To address the optimization problem of the nozzle throat to vortex chamber area ratio in vortex tubes,parameters such as the cold end pressure,cold mass fraction and baffle hole diameter were selected.Numerical simulations were conducted to investigate the effects of different inlet pressures on the working performance of the vortex tubes with different nozzle throat to vortex chamber area ratios.An empirical correlation between the optimal nozzle throat to vortex chamber area ratio and the air expansion ratio was obtained.The results show that at a certain inlet pressure,as the nozzle throat to vortex chamber area ratio increases,the cold air flow rate and refrigerating capacity of the vortex tube rise,and the cold air temperature drop,specific refrigerating capacity,isentropic cooling efficiency and coefficient of performance initially increase and then decrease.The optimal nozzle throat to vortex chamber area ratio decreases with an increase in vortex tube inlet pressure.For vortex tubes with the same structure,increasing the inlet pressure enhances the cold air temperature drop and refrigerating capacity,but reduces the coefficient of performance.In the design of vortex tubes,it is advisable to verify the resistance of the cold air flow through the baffle based on the cold air flow rate and cold orifice diameter to avoid a significant increase in nozzle backpressure,which can lead to a decline in the performance of the vortex tube.