浸没式喷水推进器壳体阻力特性及内部回流研究

Research on resistance characteristics and internal backflow of submerged waterjet propeller duct

针对典型的浸没式喷水推进器壳体,为了分析单一壳体与船体-壳体一体化结构下的阻力特性,以及涡流发生器对改善壳体内部流动分离的影响,重点分析了涡流发生器的安装方向和角度对流动控制的影响。结果表明,船体底板结构对壳体-船体结合后的阻力特性产生显著影响,壳体压力损失系数在15 m/s的来流工况下从3.42增加到3.73;采用发散布置的涡流发生器能有效抑制壳体内部上方的流动分离,并将壳体外壁的压差阻力降低了58.4%,显著提升了壳体阻力性能;适当的涡流发生器安装角度(15°)不仅能有效控制壳体内部流动分离,而且在保持进口流场均匀性的同时显著提升壳体的阻力性能。研究结果为浸没式喷水推进系统的设计提供了理论依据。

In order to analyze the resistance characteristics of a typical submerged waterjet propeller duct under the structure of individual duct and integrated structure of hull and duct,and examine the effect of vortex generators on improving internal flow separation,the analysis was focused on the effects of installation direction and angle of the vortex generator on flow control.The results show that the pressure loss coefficient of the duct increases from 3.42 to 3.73 under an incoming flow condition of 15 m/s due to the significant influence of the hull bottom structure on resistance characteristics after the duct and hull are integrated.Divergently arranged vortex generators effectively suppress the flow separation in the top part inside the duct and reduce the pressure loss resistance on the duct's external wall by 58.4%,thereby significantly improving the duct's resistance performance.An appropriate installation angle of 15°for the vortex generators not only can control internal flow separation,but also enhance the duct's resistance performance while maintaining uniformity of flow field at the inlet.These findings provide a theoretical basis for the design of submerged waterjet propulsion systems.