Design and performance study of side water inlet device of underwater vehicle engine

水下航行器发动机侧向进水装置设计与性能研究

¹ School of Marine Science and Technology, Northwestern Polytechnical University, Xi'an 710072, China
² The 705 Research Institute, China Shipbuilding Industry Corporation, Xi'an 710075, China
³ Safety and Security Service Center, Shaanxi Provincial Department of Water Resources, Xi'an 710004, China

Received: 29 February 2024

Abstract

Metal water fuel engines possess advantages such as high energy and specific impulse, simple structure, and safe and pollution-free fuel, making them suitable for underwater supercavitating vehicles. Due to the combustion chamber's internal working pressure of about 3 MPa, under the speed conditions of 40-70 m/s, the external seawater total pressure is lower than the engine's internal pressure, preventing the liquid flow from entering the engine and causing the engine to malfunction. To address this issue, this paper proposes a lateral water intake pressurization system configuration, completes the parametric design of the lateral water inlet flow channel and the pressurization pump design, and predicts the feasibility of the design results through CFD numerical simulation. The numerical simulation results of the pressurization system indicate that the total head of the device has a relative deviation of less than 5% compared to the design value, and the system can increase the incoming flow total pressure by about 4.9 MPa, and the outlet total pressure reaches 5.6 MPa, enabling the stable operation of the metal water fuel ramjet engine at a speed of 50 m/s. The research findings have reference value for the performance study of lateral water intake pressurization pump devices in water ramjet engines.

摘要

金属水燃料发动机具有高能量、高比冲、结构简单、燃料安全无污染等优势, 可用于水下超空泡航行器。由于发动机燃烧室内部工作压力约3 MPa, 在40~75 m/s航速条件下外部海水总压低于发动机内部压力, 液流无法进入发动机, 导致发动机不能正常工作。为了解决以上问题, 提出了侧向进水增压系统构型, 完成了侧向进水流道的参数化设计以及增压泵设计, 通过CFD数值仿真预测了设计结果的可行性。对增压系统的数值仿真结果表明, 装置总扬程与设计值相对偏差低于5%, 系统可将来流总压提高约4.9 MPa, 出口总压达到5.6 MPa, 能实现金属水燃料冲压发动机在航速50 m/s时稳定工作。研究成果对水冲压发动机的侧向进水增压泵装置性能研究具有参考价值。