基于数值试验及实船试航的喷水推进器改型设计

Remodel design of waterjet with CFD and its sea trial

采用基于雷诺时均法的SST湍流模型对"某轴流式喷水推进泵+进水流道+船体"系统进行数值计算,查找出了该喷水推进泵和进水流道设计存在的一些问题。依据该船体阻力、设计航速和主机功率等参数重新对该船喷水推进器进行选型,进而运用三元的方法对喷水推进泵进行设计,利用参数化设计的方法对流道进行设计。采用了数值试验的方法校核新设计的混流式喷水推进器流体动力性能,计算结果表明:新设计喷水推进泵和进水流道性能优异,并且能够较好地满足快速性指标。最后,对改进设计的喷水推进器进行了快速性预报和实船试航,试航结果表明新设计混流式喷水推进器推进航速超过设计航速9.4%,并且数值预报航速与试航结果误差为1.5%,这既验证了设计方法的有效性,也验证了所采用的数值模型的准确性。

A ‘axial-flow pump ＋ duct ＋ hull’ system’s performance was calculated by solving RANS equa-tions and SST turbulent model equations, and the faults of the waterjet design were showed by analyzing the fluid flow characteristic of waterjet pump. The new design parameters for waterjet were calculated based on the craft resistance curve and the main parameters of engine. Then the mixed-flow pump was redesigned by three-dimensional design method, and the duct was gained by parametric design method. The perfor-mance of the new waterjet was calculated by CFD method, which indicated that the pump and inlet duct had excellent performance, and the desired craft speed was well satisfied. Finally, the self-propulsion test of the ship with remodeled waterjet was carried out, the maximum speed of the ship exceed the design speed by 9.4%, and the calculated speed of the ship from CFD agrees well with test data with the error of 1.5%, which validates credibility of the numerical model and the design method.