两用斜流式喷水推进系统研究

Research on a two-function mixed flow waterjet propulsion system

开发了一种摩托艇推进和水上飞行两用斜流式喷水推进系统,并对其进行了研究.首先建立了喷水推进器的推力与水力特性流量、扬程、比转速以及射流比之间的联系并由此确定了水力性能参数.然后设计了3个具有不同射流比的喷水推进器并应用数值计算对得到的外特性以及推力特性进行比较分析,研究发现根据所确定的计算方法得到的喷水推进器在接近最优效率点工作,推力满足喷水推进的要求,推功比也接近最大推功比.最后以设计得到的喷水推进器为动力源、以应用能量最小为优化目标对水上飞行喷射装备进行设计分析,得到了水上飞行工况时喷水推进器的运行范围,进一步完善了喷水推进器的设计理论和分析方法.

A mixed flow waterjet propulsion system for both flying on water and ship propulsion was developed and studied. Equations involving parameters capacity,head,specific speed and jet ratio were firstly deduced according to the thrust formula and the specific speed expression and solved to calculate the hydraulic variables.Three mixed flow waterjet propulsion devices with different jet ratio were developed and were numerically simulated to analyze their overall performance by comparison. The comparison indicated that the thrust agreed with the required one,the operation condition matched with the best efficiency point very well and the thrust-power ratio was close to the maximum one. Therefore the calculation process illustrated is of course reasonable. Lastly,a flying equipment that was connected with the waterjet propulsion by a soft pipe and supported a flying device by two jet nozzles was optimized to determine the pipe diameter and the nozzle diameter based on the objective of utilizing the lowest energy. The efforts for the calculation and analysis are useful for waterjet propulsion design.