针对某型航空发动机,在其安装结构的主要承力构件上进行应变计布置和桥路设计.分别对发动机安装结构部件和结构整体进行载荷标定试验,以此建立结构应变输出与载荷输入关系方程.并在此过程中对推力的标定方程进行相关性和显著性分析,相关系数和F值分别达到0.999和22 000以上.推力计算值与加载载荷比较,单向和两向加载的工况下误差均在2%以内.结果表明:标定方程具有较高的精度.将标定方程代入实测飞行数据,得到发动机推力-时间历程曲线,与发动机燃油流量-时间历程曲线进行对比,两者变化趋势相吻合,进一步验证了发动机推力载荷测试方法的有效性和可行性,为飞机实际飞行时航空发动机推力的测量提供了一种可实施的技术途径.
For a certain aero-engine, strain gauges layout and bridges design on the main load-bearing components of areo-engine installation structure were carried out. To establish the relationship equations between strain output and load input, load calibration tests were conducted on the installation structure components and the whole structure respectively. And the correlation and significance for calibration equation of the thrust was analyzed in this approach. The results of correlation coefficient and F-measure reached more than 0. 999 and 22000 respectively. Comparing the thrust calculations and load values, the errors under one- direction and two-direction were less than 2%. Results show that calibration equation has high accuracy. With introduction of the flight data into calibration equations, the engine thrust-time history curve was obtained. By contrast, the developmental trends of engine thrust-time history curves and engine fuel flow-time history curves coincided well. The results verify effectiveness and feasibility of the engine thrust test method further, and provide an enforceable technical approach for engine thrust measurement in actual flight.