水下喷雾发动机非设计点性能分析

Analysis of Off-Design Performance for Mist Jet Engine

关键词:  喷雾发动机  水下航行  非设计工况  数值模拟 

Key words:  Mist jet engine  Underwater movement  Off-design points  Numerical simulation

摘要:

针对水下喷雾发动机非设计工况下运行特性,建立数学模型并开展数值模拟研究,分析了航行体速度及环境压力对发动机性能的影响等,以期全面了解发动机特性,为其设计工作奠定理论基础。计算结果表明:当发动机应用于航行速度大于发动机设计速度的航行体时,需增大通入气体质量流率,但发动机推力略有减小,推进效率增大；环境压力大于发动机设计工况时,需减小气体质量流率,同时发动机推力及推进效率均减小。通过反馈控制调节气体质量流率及压力,可使发动机动力输出满足航行体一定速度范围内航行的推力需求。 

Abstract:

To predict the off-design performance of mist jet engine, the mathematical models were constructed under some assumptions. The thrust and propulsion efficiency were obtained by numerical simulation. The effects of ship velocity and ambient pressure on the performance were emphatically investigated for a comprehensive understanding of mist jet engine. When the ship velocity is higher than the design value,the gas mass flow rate must be increased. In this condition, the engine works with higher efficiency and less thrust. With increasing ambient pressure,less gas needs to be injected, but the thrust and propulsion efficiency of the engine decrease. By means of regulating the gas mass flow rate and initial pressure with feedback, it can drive the engine output the thrust close to the drag of the vehicle with varied velocity. 