基于模型修正的高空起动预测方法

High-altitude Starting Prediction Method Based on Model Correction

针对利用基于部件特性的起动模型预测发动机起动过程时精度较低的问题,通过建立起动模型迭代求解方程研究了起动模型计算方法。基于燃烧效率修正系数、吸放热模型换热系数、附加损失修正系数,匹配发动机起动关键参数,研究了模型修正方法;基于发动机部件特性的起动模型,结合地面起动数据修正,实现了模型计算数据与试验数据基本一致,并验证了起动模型修正的有效性。利用该模型进行空中起动预测,并将模型预测结果与试验结果进行了对比。结果表明:起动试验得到的压气机共同工作线、转子加速率与模型修正结果比较吻合,涡轮出口排气温度差异合理。起动模型修正方法可以高效支撑高空起动试验的开展,在空中起动试验包线边界工况点上,起动试验能够一次成功,降低试验风险和试验成本。

In response to the problem of low accuracy in predicting engine starting process using starting models based on component characteristics,the calculation method of the starting model was studied by establishing an iterative solution equation for the starting model.Based on the correction coefficient of combustion efficiency,the heat transfer coefficient of the heat absorption and release model,and the additional loss correction coefficient,the key engine starting parameters were matched and the model correction method was studied.Based on the starting model derived from engine component characteristics and combined with the ground starting data,the model-calculated data was consistent with the test data,and the validity of the starting model correction was verified.The model was used to predict air starting and compared with the test results.The results show that the compressor common working line and rotor acceleration rate of the starting test are in good agreement with the corrected model,and the difference in the turbine outlet exhaust gas temperature is reasonable.The starting model correction method can efficiently support high-altitude starting tests,make air starting tests at boundary working points of the starting envelope successful in one go,and reduce test risk and cost.