喷管角度对脉冲爆震发动机性能影响数值研究

Numerical Simulation of the Nozzle Angle Effect on PDE Performance

为了研究喷管角度对脉冲爆震发动机性能的影响,以丙烷和空气分别为燃料和氧化剂,对采用不同收敛角和扩张角喷管的脉冲爆震发动机工作过程进行了单循环数值模拟。研究结果表明,收敛喷管的收敛角和扩张喷管的扩张角对脉冲爆震发动机性能的影响规律是不同的。收敛喷管出口要比扩张喷管出口更早地形成膨胀波系,扩张喷管出口膨胀得要比收敛喷管出口膨胀得更为充分。对于收敛喷管而言,无论收敛角度如何变化,都会有正的推力增益;对于扩张喷管,当扩张角度超过9°时,就会产生负的推力增益。喷管收敛角为9°时的脉冲爆震发动机性能较好。

In order to investigate the effects of nozzles with different angles on PDE performance, PDE with nozzles of different convergent and divergent angles was simulated and propaneair mixture was used. The simulation results indicated that the effects of nozzles with different angles on PDE performance were not the same. While a series of expansion wave appeared earlier in the outlet of the convergent nozzle, the gas expanded perfect in the outlet of the divergent nozzle. For the PDE with convergent nozzle, the thrust augmentation was always positive no matter how the convergent angle changed. For the PDE with a divergent nozzle, there was a thrust loss with a divergent angle of over 9°. When the nozzle convergent angle was 9°,PDE obtained the highest performance.