带输出轴的直升机进气道设计改进

利用自主软件NAPA对典型带输出轴的直升机进气道进行了三维流场数值分析,通过修正进气道输出轴迎风侧的管道曲率半径、在背风侧增添优化的尾锥,改进设计了原型进气道并进行了模拟.结果表明,原型进气道由于输出轴堵塞了流道,使输出轴背风侧存在很大的分离,同时迎风侧存在转弯损失,导致出口面流场畸变严重.改型进气道减小了输出轴背风侧的分离和迎风侧的转弯损失,使其既保持了高总压恢复系数,且畸变指数最大降低了74%.

Study of modifying helicopter inlet containing output shaft

A typical helicopter inlet containing output shaft was studied by three-dimensional turbulent numerical calculation code NAPA in this paper.The inlet was redesigned by modifying the curvature of upwind side of the inlet and adding an optimal spike on the backward of output shaft,and then simulated using NAPA program.The results show that,as output shaft blocks the flow path in the original inlet,there is a large separation zone behind the shaft and a turn loss in upwind of the shaft,thus inducing a serious distortion in the inlet.By modification,the separation zone behind the shaft and turn loss at upwind side are reduced.Modifying inlet maintains high pressure recovery,and the distortion index is reduced by 74% at most.