航空发动机推力测量台架原理误差分析

为研究影响航空发动机推力测量台架系统原理误差的因素及作用,针对发动机弹簧片支撑式推力测量台架,以推力偏心假设为基础建立其力学模型,采用理论分析和仿真验证相结合的方法对某试车台架进行原理误差分析.在给定条件下,台架在竖直平面和水平面内的角偏心远小于推力角偏心,并不会对推力测量造成显著影响,台架结构变形引起的角偏心也很小.相比之下,原理误差影响最大的因素依次为推力角偏心、热变形和弹阻力,原理误差分别为0.38％、0.16％和0.04％,应加以控制.当推力偏心量造成的原理误差不能满足精度指标时,需采用原位加载系统或者矢量推力测量台架来评估.

Principle Errors Analysis of Thrust Measurement Test Bench System for Aeroengine

To study the factors and function of principle errors which influenced thrust measurement test bench system, that supported by spring for aeroengine, established mechanical model based on thrust eccentricity assumption, the principle errors of an aeroengine test bench were analyzed using both theoretical analysis and simulation. Under a given condition, the angle eccentricity of the stand in vertical and horizontal plane was much smaller than that of thrust eccentricity, it will affect on thrust measuring indistinctively, and the eccentric angle caused by malformation of test bench system is very small. On the contrary, from most to least, the influence factors on principle errors analysis are thrust eccentricity, thermal deformation and spring resistance, principle errors are 0.38%, 0.16% and 0.38% respectively, and all the factors should be controlled. When principle errors from thrust eccentricity are over accuracy, the situ-calibration system or vector thrust measurement should be used for assessment.