中文摘要：

为探究格栅安装角对喷水推进泵装置性能的影响,建立了＂格栅＋推进泵＋进水流道＋喷嘴＋船底水体＂的三维几何模型,基于计算流体动力学（CFD）技术对该模型进行数值计算,并对内流场特性、推力性能和水力性能展开分析.分析结果表明：格栅的安装会明显缩小泵装置纵剖面上的高速区范围,但格栅安装角对高速区范围变化影响不大;装设格栅后弯管断面和流道出口断面上的法向流速分布明显变化,随着安装角的增加,该影响减弱;流道出口断面水流较为平顺,法向流速均匀度欠佳,格栅的安装会加剧这种趋势;装设格栅后装置的推力减小,随着格栅安装角的增加,推力会逐渐恢复至无格栅方案时的推力水平;格栅安装角的变化对装置的水力性能影响并不明显;推荐格栅安装角γ选择5°.

英文摘要：

The protecting grid is used to avoid the impeller damaging from garbage in the water,and it also affects the performance of the waterjet propulsion system.The 3-D geometrical model which consists of the protecting grid,propulsion pump,passage inlet,nozzle and the water body under the ship is built and simulated numerically by CFD software so that the effect of the setting angle of the waterjet propulsion system on the performance of the waterjet propulsion system is discussed.The conclusions below can be draw：the area of high velocity zone on the middle profile of the device with protecting grid decreases and the setting angles have small influence on the area of high velocity.There is an obvious change of the normal velocity distribution on both belt pipe section and passage outlet section when the protecting grid is installed,this kind of change deceases as the setting angles increases.The water flows smoothly on the passage outlet section,but the normal velocity uniformity is not desirable,the trend expands when the protecting grid is installed.The thrust gets smaller when the protecting grid is installed.As the setting angle gets bigger,the thrust recovers to the value of the original case in which there is no protecting grid installed gradually.No evident effect on the hydraulic performance as the setting angle changes.It’s recommended that the setting angle of protecting grid is 5°.