喷水推进泵内精细流场测试研究

Test study of delicate flow field in waterjet propulsion pump

为研究喷水推进泵内复杂的精细流场结构,针对一典型喷水推进泵水力模型,采用粒子图像测速(PIV)技术,在喷水推进泵内入口段、叶轮流道、导叶流道及导叶出口四个位置开展速度场的多工况测量,经图像处理及分析,得到了不同位置的速度场及流场结构,并采用本征正交分解(POD)方法对导叶体出口处速度场进行能量分析.结果表明:导叶出口速度场重复性偏差为1.66%,测试方法的重复性精度较高;小流量工况下,叶轮流道内存在由轮毂向轮缘的径向分速度,脉动速度增大;额定流量下,二次流和脉动速度减小,流场趋于均匀;导叶内流场受到叶轮出流影响,在小流量和额定流量工况下,导叶出口一、二阶模态能量占比分别为4.2%,3.8%和5.2%,2.6%.

To study the complex delicate flow field structure in the waterjet propulsion pump,the particle image velocimeter(PIV)technology was adopted for a typical waterjet propulsion pump model to measure the velocity field in the inlet section,the impeller channel,the guide channel and the guide vane outlet.After image processing and analysis,the velocity field and flow field structure of different positions were obtained,and the proper orthogonal decomposition(POD) method was used to analyze the energy of the velocity field at the guide vane outlet.Results show that the repeatability deviation of the guide vane outlet velocity field is 1.66%,which indicates the repeatability accuracy of the test method is relatively high.Under the small flow condition,the radial velocity component from the hub to the tip of the impeller flow path exists and the pulse velocity increases.Under the designed flow rate,the secondary flow and the pulsation velocity decrease,and the flow field tends to be uniform.The internal flow field of the guide vane is affected by the outflow of the impeller.Under the small flow rate and the designed flow condition,the energy ratio of the first and second order mode is 4.2%,3.8%,and 5.2%,2.6%,respectively.