小涵道比涡扇发动机动态特性数值计算

研究了涡扇发动机动态数学模型以及数值模拟方法,对于进口条件变化、发动机加速、发动机减速、发动机加力等情况下动态工作过程,改进的发动机动态性能数值模拟程序具备了数值仿真的能力,并对小涵道比涡扇发动机动态特性进行了数值计算分析,结果表明:对于飞行条件快速变化的情况,当发动机推力增大到一定程度后,会有逐渐减小的趋势,而缓慢变化时,就没有这种振荡现象;对于燃油质量流量增大、减小情况,变化的快慢对应耗油率的峰值是不同的;同样,随着加力温升的变化速度不同,发动机推力和耗油率达到的峰值也不同.

Numerical calculation of dynamic performance of low-bypass ratio turbofan engine

The dynamic mathematical model and numerical simulation methods of turbofan engine were investigated.The modified engine dynamic performance numerical simulation program could simulate the engine dynamic conditions,such as changes of the inlet parameters,engine maximum rating after burning,engine acceleration and deceleration;then,dynamic performance of low-bypass turbofan engine was analyzed.The numerical simulation results show that engine thrust drops gradually within some accretion range while the inlet parameters change quickly;on the contrary,there isn't thrust surge while the inlet parameters change slowly.History of maximum specific fuel consumption is different while change speed of fuel flux accretion and diminution is unlike.Similarly,the maximum engine thrust and specific fuel consumption may vary with temperature rise.