摘要
基于求解雷诺平均的Navier-Stokes方程组,对鱼雷燃气涡轮机斜切喷管内流场进行了数值模拟计算,研究了斜切喷管气动特性随膨胀比的变化关系。数值模拟结果表明,该文所使用的数值模拟方法能够较好地捕捉斜切喷管内部存在的各种复杂流动结构,合理地预测了斜切喷管内部流场随膨胀比的变化趋势;喷管处于膨胀过度状态时,喷管出口会出现激波,造成激波损失,激波与边界层干涉,使得流动损失进一步增大,引起喷管气动性能的迅速恶化,设计时应尽量避免;对于既定尺寸的喷管,膨胀比大于临界流量膨胀比时,通过喷管的燃气流量保持最大流量不变。
A three-dimensional, viscous, steady computational fluid dynamics (CFD) analysis is performed for investigating the flow field in the scarfed nozzle of a torpedo turbine by solving RANS-Navier-Stocks equations and RNG κ-ε turbulence model. The flow detail and performance of the nozzle are studied in varying pressure ratio conditions. Numerical simulation results show that the inner complex flow characteristics in the scarfed nozzle are predicted. When the nozzle is in over-expansion state, the shock wave and flow separation appear at nozzle outlet, and the performance is degraded rapidly with the pressure ratio increasing. This situation should be avoided in nozzle design. As the pressure ratio is larger than the one at critical mass flow rate, the mass flow rate of the nozzle keeps the maximum.
出处
《鱼雷技术》
2010年第3期223-227,共5页
Torpedo Technology
关键词
鱼雷涡轮机
斜切喷管
数值模拟
torpedo turbine
scarfed nozzle
numerical simulation