调距桨梢涡精细流场的数值模拟

Numerical simulation of tip vortex local flow of controllable pitch propeller

为验证湍流粘度取为mk/的修正剪切应力输运(SST)湍流模型在螺旋桨梢涡精细流场粘性模拟中的适用性,对驱逐舰母型桨DTMB5168调距桨的梢涡流动进行了模拟与校验。结果显示:0.9R以上径向区域周向平均的轴向、周向和径向速度分量均与试验值吻合很好,但0.9R以下区域的径向速度分量存在一定偏差;0.7R和0.92R处沿周向变化的三个速度分量变化形态均与试验值一致,故可由此来确定梢涡涡核区,但周向和径向速度分量峰值比试验值略小;轴向0.3R距离内梢涡涡核运动轨迹的模拟结果与试验值吻合较好。由此证明了修正的SST湍流模型在螺旋桨梢涡流动模拟中的适用性,还表明由叶梢区的径向、周向和轴向方向以及桨叶近壁面法向、叶截面弦长方向和尾流轴向方向的网格节点密度来局部控制叶梢区流动的模拟效果的可行性。

To qualify the modified SST turbulent model with μ1 = Pmk/w in propeller tip vortex local flows prediction, numerical simulation of DTMB5168 controllable pitch propeller＇s tip vortex flow was conducted. Results show that, the circumferentially averaged axial, circumferential and radial velocity components outside 0.9R radial region all agree very well with the experiment, but the radial velocity component inside the 0.9R line shows a little discrepancy. The tendencies of the threevelocity components＇ variation with circumferential position are in consistent with the experiment, and the tip vortex core region can be determined by two peaks of circumferential velocity. But the peaks of the circumferential and radial velocities are also little under-predicted. In addition, the predicted tip vortex trajectory fits well with the experiment within 0.3R axial distance. The results show the applicability of the modified SST turbulent model in tip vortex flow simulation and the feasibility to improving the tip local flow simulation by adjusting the density of the mesh nodes in tip radial, circumferential and axial direction, blade surface normal direction, blade sections＇ chord-wise direction, as well as the wake axial direction.