【摘要】 针对某型喷水推进器的进水流道的斜背区域，设计了双孔射流旋涡发生器(VGJ),以抑制低进速比(IVR≤0.7)工况下边界层流动分离。采用SST k-ω湍流模型对不同进速比下的喷水推进泵内部流动进行数值模拟，对比分析了VGJ控制推进泵进流的畸变程度以及对泵内压力脉动频谱特性的影响。结果表明：在IVR=0.5工况下，VGJ显著降低了进水流道的出流畸变，使喷水推进器推力和推进效率分别提升了22.61%和21.88%;进流畸变引发的轴频压力脉动幅值比叶频脉动高90%,且导叶内压力脉动幅值沿叶轮周向呈现方向性分布，经VGJ控制后，压力脉动幅值下降了1/3;VGJ可有效抑制推进泵进流畸变，改善推进泵水力性能，降低泵内流体的压力脉动，表明该技术在喷水推进器的减振降噪方面具有良好的应用前景。更多还原

【Abstract】 A pair of vortex generator jets(VGJ) were designed on the inclined back of the inflow runner in a waterjet propulsion system to mitigate flow separation of boundary layer under low velocity ratio conditions(IVR≤0.7). Numerical simulation of flow in waterjet propulsion pump at different inlet flow ratios was conducted using the SST k-ω turbulence model, comparing the effects of VGJ on the inlet flow distortion and the spectral characteristics of pressure fluctuations inside the propulsion pump. The results indicate that under the working condition(IVR=0.5), VGJ significantly reduces the outlet flow distortion of the inflow runner, leading to a 22.61% increase in thrust and a 21.88% improvement in propulsion efficiency for the waterjet propulsion system. The axial-frequency pressure fluctuation magnitude induced by inlet flow distortion are found to be 90% higher than the blade-passing frequency fluctuations, with directional pressure fluctuation patterns observed along the impeller circumference within the guide vane. After VGJ control, the amplitude of pressure fluctuations decreases by one-third. Overall, VGJ effectively reduces inlet flow distortion of propulsion pump, enhances the hydraulic performance of the propulsion pump, and suppresses the pressure fluctuations in pump, demonstrating good application potential for vibration and noise reduction in waterjet propulsion systems by this technology.更多还原