飞机起飞滑跑发动机推力数值确定方法

利用数值理论对飞机起飞滑跑距离计算中发动机瞬时推力的确定方法进行了研究,提出以发动机推力曲线图中已知推力曲线为基础,通过拉格朗日插值确定未知推力的算法。基于所提算法,对某型飞机在2 000 m压力高度上的推力进行计算,并与从推力曲线查到的实际数据比较,二者的平均相对误差为3.2‰。用所提算法确定推力,对该型飞机在5种条件下的起飞滑跑距离进行计算,计算结果与实际滑跑距离的平均相对误差为3.0%。计算结果表明,算法是准确可行的。

A Numerical Value Confirmation Method of Engine Thrust in Aircraft Take-off Running

The confirmation method of engine instantaneous thrust in aircraft take-off running distance calculation was studied by numerical value calculation theory.An algorithm of Lagrange interpolation to confirm engine instantaneous thrust was put up.Based on the engine instantaneous thrusts that can be found in the figure of engine thrust curve,the algorithm can calculate the engine instantaneous thrusts that can′t be found in the figure of engine thrust curve.Based on the algorithm,the instantaneous thrusts of a certain aircraft′s engine in pressure height of 2 000m were computed.The average relative error between computation result and actual instantaneous thrusts is 3.2‰.Furthermore,5 kinds of take-off running distances of the aircraft were computed.The average relative error between computation results and actual running distance is 3.0%.The results indicate that the algorithm is precise and feasible.