Numerical simulation of LWC changes in S-duct inlet

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.