蒙特卡洛法在发动机推力测量不确定度评估中的应用

现行对发动机试验推力测量不确定度的评估一直采用GUM法,存在输入量和输出量概率分布假设以及非线性模型近似等问题,有一定的局限性;以发动机推力矢量测量为例,文中简述了压电式推力矢量测量的数学模型,运用GUM法对推力矢量参数的不确定度评估,同时分析了蒙特卡洛法的原理、具体评估过程和适用性,编制了软件,并将不确定度评估结果与GUM法评估结果进行对比;对比结果表明,在发动机试验推力矢量参数的不确定度评估过程中,蒙特卡洛法相比GUM法更为适用.

Application of Monte Carlo Method in Uncertainty Evaluation of Engine Thrust Measurement

The GUM method has always been used to evaluate the uncertainty of the thrust measurement of the engine test. There are problems such as the assumption of the probability distribution of the input and output and the approximation of the nonlinear model, which have certain limitations. Taking engine thrust vector measurement as an example, the article briefly describes the mathematical model of piezoelectric thrust vector measurement, uses GUM method to evaluate the uncertainty of thrust vector parameters, and analyzes the principle, specific evaluation process and application of Monte Carlo method. The software was compiled and the uncertainty evaluation result was compared with the GUM method evaluation result. The comparison results show that the Monte Carlo method is more suitable than the GUM method in the process of evaluating the uncertainty of the thrust vector parameters of the engine test.