低红外特征涡扇发动机加速控制及影响规律研究

Acceleration control and influence law of low infrared characteristics turbofan engine

关键词:  涡扇发动机  排气系统  红外辐射  加速控制计划  序列二次规划

Key words:  Turbofan engine  Exhaust system  Infrared radiation  Acceleration control plan  Sequential quadratic programming

摘要:

为探究红外抑制措施对发动机加速性能的影响，提出并制定了针对发动机排气系统外涵引气冷却的普适性加速控制计划，开展了低红外特征涡扇发动机加速控制及其影响规律研究。首先，建立了带外涵道引气冷却中心锥、全遮挡导流支板和尾喷管扩张壁面的发动机部件级模型，并在此基础上发展了排气系统正后向红外辐射特征计算模型；其次采用可行序列二次规划算法，针对采用了不同排气系统红外抑制措施的涡扇发动机分别制定加速控制计划；最后通过硬件在回路仿真验证上述加速控制计划对带红外抑制措施的发动机从慢车到中间状态加速过程的有效性。结果表明，与常规涡扇发动机相比，采用了高温壁面冷却虽然能降低发动机近50%的红外辐射特征，提高战机的隐身性能，但会导致发动机推力降低近6%，油耗上升4%以上，加速时间延长20%左右。

Abstract:

In order to explore the influence of infrared suppression measures on engine acceleration performance， a universal acceleration control plan for the exhaust system with bleed air cooling of the engine was proposed and formulated， and the acceleration control of low infrared turbofan engine and its influence law were studied. Firstly， a component-based model of the engine with bleed air cooling center cone， the fully shielded guiding strut and the inner wall of nozzle expansion section is established， and the forward and backward infrared radiation characteristic calculation model of the exhaust system is developed on this basis. Secondly， the feasible sequential quadratic programming algorithm is used to formulate acceleration control plans for turbofan engines with different exhaust system infrared suppression measures. Finally， the hardware in the loop simulation verifies the effectiveness of the above acceleration control plan for the acceleration process of the engine with infrared suppression measures from idle to intermediate state. The results show that compared with the conventional turbofan engine， the adoption of high temperature wall cooling can reduce the infrared radiation characteristics of the engine by nearly 50% and improve the stealth performance of the fighter， but it will reduce the engine thrust by nearly 6%， increase fuel consumption by more than 4%， and prolong the acceleration time by about 20%.