定容燃烧器法热损失率不确定度分析

定容燃烧器法是一种测试高压下固体推进剂燃速特性的方法。定容燃烧器法工作过程中散热损失是影响燃速测试精度的主要因素。推导了热损失率计算方程,分析了各因素对热损失率的影响;建立了热损失率测试结果的不确定度评定方法,并对测试结果进行了不确定度评定。研究表明,推进剂试样燃面、燃气定容比热、燃气压强、燃气温度是影响热损失率不确定度的主要因素,其中燃面是影响热损失率不确定度的最大因素;后续实验中必须提高推进剂试样尺寸加工精度,减小推进剂试样燃面误差。

Uncertainty Analysis of Heat Loss Rate by Constant Volume Burner Method

The constant volume burner is a kind of test method to measure the burning rate of solid propellant under high pressure. Heat loss of the constant volume burner is one of the most important factors affecting the test accuracy of burning rate. Heat loss rate equation was derived to study the various factors on the rate of heat loss. The assessment method of the uncertainty of heat loss rate has been established, and the uncertainty also has been obtained. According to the study, it was known that the sample propellant burning surface, the gas constant volume specific heat, gas pressure, gas temperature are main factors of the uncertainty of the heat loss rate, and burning surface is the most important factor. The precision of propellant sample size should be increased to reduce the deviation of propellant burning surface of the sample.