喷嘴结构对去旋系统减阻特性影响的数值研究

Numerical Investigation on Effects of Varied De-Swirl Nozzle Configurations on Drag Reduction Performance of De-Swirl System

为了探索去旋喷嘴式减涡器的结构变化对共转盘腔径向内流压力损失的影响规律,对不同转速和喷嘴结构下的去旋系统开展了数值研究,获得了不同工况下径向内流流场结构以及压力损失的分布曲线。研究表明:去旋喷嘴可有效提高共转盘腔内压力损失开始急剧增长的临界转速;方形喷嘴与圆形喷嘴降低压力损失效果接近;缩小喷嘴入口方向与气流旋转速度方向之间的夹角可有效改善喷嘴的进气条件;同一周向位置,喷嘴总流通面积保持不变,沿轴向增加喷嘴数目会造成更多的压力损失。

To research the effects on drag reduction performance of de-swirl nozzle configuration, numeri- cal simulation was carried out to calculate the radial inflow of gas in co-rotating disc cavities with varied de-swirl nozzles under different rotational speeds. The flow structures and the diagrams of pressure loss under varied condition were obtained. The resuhs show that the use of de-swirl nozzles is valid for putting off the increase of pressure loss. The effects of the nozzles with square cross section and circular cross section on reducing the pressure loss is very close. Reducing the angle between the entrance direction of de-swirl nozzles and the direction of airflow is effective on reducing the pressure loss caused by the de-swirl nozzles themselves. When the total flow area is constant, the increase of the de-swirl nozzle amount along the axial direction under the same circumferential position is profitless for reducing the pressure loss.