为揭示集水箱内水雾雾滴喷射的初始位置对喷嘴喷雾冷却性能的影响，利用欧拉-拉格朗日方法和离散相模型对发动机排气集水箱内横流喷雾冷却过程进行了三维数值模拟。结果表明：当雾滴进入烟气流场的初始位置距离分隔板小于0．14 m时，部分雾滴进入循环涡流区，大量雾滴与分流管管壁反复碰撞，在管壁上形成液膜，使得雾滴蒸发速率降低；当雾滴初始位置位于（0．14，0．23） m时，两相掺混较好，且随着距离的减小，雾滴有效运动行程增加，喷雾冷却效果增强；当雾滴初始位置大于0．23 m时，雾滴未在排气室进行螺旋运动而是随气流直接排出集水箱，蒸发时间短，喷雾冷却效果不显著。%In order to reveal the effect of the initial spray location of water droplets on the cooling per-formance of the nozzles ,the Eulerian-Lagrangian method and the discrete phase model are used for the three-dimensional CFD simulation of cross-flow spray cooling in the water-collecting box (WCB) of an engine exhaust system .Studies show that w hen the initial spray location at w hich droplets enter the gas flow field is less than 0 .14 m ,some droplets will fall into circular vortex and collide repeatedly with the fine tubes to form a liquid film which can decrease the evaporation rate of water droplets ;when the nozzles are located in the zone of (0 .14 ,0 .23) m ,the two phases will mix well and the ef-fective process of droplets and the effect of spray cooling will increase as the length between the clap-board and the initial spray location decreases ;and w hen the initial spray location is more than 0 .23 m , the droplets will directly move out of the WCB without screwy motion in the exhaust chamber ,which leads to an unremarkable spray cooling effect due to a shorter evaporation time .
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