扩散段变面积比对超音速喷管非平衡凝结性能的影响

The effects of diffuser area ratio on non-equilibrium condensation inside supersonic Laval nozzle

本文研究了拉法尔喷管扩散段变面积比情况下,内部超音速非平衡凝结过程.在Fluent软件建立二维喷管湿蒸汽模型,通过用户自定义函数引入三系数维里型水蒸气状态方程.利用Moore喷管的实验数据对湿模型进行校正,验证了模型的准确度,在此基础上将湿蒸汽模型与理想气体模型进行对比,从中可以看出非平衡冷凝对流体具有增压、降速和升温的作用,最后,研究扩散段变面积比情况下,超音速喷管内非平衡凝结性能的变化情况,可以看出冷凝的强度随扩散段面积比的增大而减小,但是冷凝水的含量会随面积比的增大而增大,因此,为了同时降低冷凝强度与冷凝水的含量需要选择合适的扩散段面积比.

In the present paper,the effects of diffuser area ratio on non-equilibrium condensation inside supersonic laval nozzle was investigated in fluent,2-D laval nozzle wet steam model was enhanced by user defined third virial steam equations,which was vali dated by experiment data of Moore.and then,wet steam model was compared with ideal gas model,from which it can be revealed that non-equilibrium condensation inside laval nozzle has the function of maintaining static pressure,reducing mach number and el evating static temperature.Finally,the effects of diffuser area ratio on non-equilibrium condensation inside supersonic laval nozzle were investigated.it is shown that the condensation intensity decrease while mass liquid fraction increase with the increase of diffuser area ratio,so in order to reduce both condensation intensity and mass liquid fraction,proper diffuser area ratio should be carefully considered.