水下航行器对转涡轮发动机输出扭矩计算及仿真

Theoretical and Simulation Study on Output Torque of Counter-rotating Turbine for Underwater Vehicle

对转涡轮发动机因其在效率、质量、陀螺力矩等方面所具有的优势,为水下航行器增大航速和航程提供了巨大动力。文中提出了一种水下航行器发动机利用对转涡轮进行工作的新方法。通过分析对转涡轮发动机结构特点,给出了水下航行器发动机在利用对转涡轮情况下一级涡轮和二级涡轮有效输出扭矩的理论推导;定义了三速制工况模式,以中间工况设计喷嘴和一级涡轮参数,以高工况设计二级涡轮参数;建立了对转涡轮发动机的仿真模型,进行了3种工况模式的流场仿真。通过对理论计算值和相关仿真结果进行对比发现,水下航行器使用对转涡轮代替常规涡轮,可以大幅减小余速损失,提高涡轮发动机效率,证实文中提出的方法正确且可行。

A new parameter design of counter-rotating turbine engine for an underwater vehicle is presented. The structure characteristics of counter-rotating turbine are analyzed to derive mathematical expressions of effective output torque for the first-stage and the second-stage turbines. Three working modes with different velocities are designed for an underwater vehicle. The nozzles and the first-stage turbine are designed based on the medium velocity mode, while the second-stage turbine is designed based on the highest velocity mode. Furthermore, a model of counter-rotating turbine engine is built to simulate the flow fields for the three working conditions. Comparison between the theoretical calculation results and the simulation results indicates that substitution of the counter-rotating turbine for the conventional turbine can reduce the residual velocity loss and improve the efficiency of the turbine engine, suggesting the correctness and feasibility of the proposed method.