S弯进气道中液态水含量变化的数值模拟研究  

Numerical simulation of LWC changes in S-duct inlet

作　　者：张丽芬[1] 刘振侠[1] 胡剑平[1] 

机构地区：[1]西北工业大学动力与能源学院,西安710072

出　　处：《应用力学学报》2013年第6期833-838,950,共6页Chinese Journal of Applied Mechanics

摘　　要：为了改善目前直接将大气液态水含量(LWC0)作为发动机进口结冰计算参数的研究现状,对某S弯进气道的LWC变化进行了数值模拟。采用欧拉-拉格朗日方法计算了进气道内空气-水滴两相流场,得到了流场液态水含量的分布;分析了不同的流量系数下大气液态水含量、水滴直径、Ma对进气道出口LWC的影响。计算结果表明:受S弯的影响,进气道出口的液态水含量分布不均匀,中间液态水含量较高,顶部和底部较少;流量系数φ<1时比φ>1时的出口平均LWC高,且高LWC区域也较大;在流量系数一定的条件下,水滴直径增加,进气道出口平均LWC减小;大气中LWC0增加,进气道出口LWC分布不变,但LWC值会增大;Ma增加,进气道出口平均LWC变化不大。由于进气道出口LWC的数值及分布与大气中的LWC0存在一定差别,因此研究发动机支板的结冰、防冰问题和发动机帽罩的结冰、防冰问题时,需要考虑进气道的影响。The changes of LWC in S-duct inlet are simulated to improve the study of using LWC in atmosphere as the computational parameters in icing calculation of aero-engines. The Navier-Stokes equations are solved for the air, and the Lagrange method are used to the droplets. The distribution of the LWC in the S-duct is obtained. Influences of different LWC in atmosphere, droplet diameter and Mach number on LWC in S-duct outlet under the same flow coefficient condition are analyzed. Results obtained show that: with the influence of the geometry of S-duct, the LWC values in the center of the outlet are high and on the top and bottom are low; the average value of LWC is high when the flow coefficient is less than one, and the area of high LWC is large; under the same flow coefficient condition, with increase of droplet diameter, the average value of LWC on outlet of S-duct inlet are reduced; with increase of LWC in atmosphere, the distribution of LWC on outlet is unaltered, but the LWC value on outlet is increased; with increase of incoming Mach number, the LWC value on outlet has a little change. The LWC on outlet of S-duct inlet is different from that in atmosphere, so the effect of S-duct geometry on LWC should be taken into account in icing calculation of vane and nose cone of aero-engine.

关 键 词：S弯进气道 液态水含量 结冰 拉格朗日法 数值模拟 

分 类 号：V233.94[航空宇航科学与技术—航空宇航推进理论与工程]