【摘要】 建立了适用于单窗调制型热喷涂粒子参数热辐射检测系统的数据处理方法,并应用模拟和实测数据进行了效果评估.结果表明:预处理宜采用低通滤波基础上的算术补偿去除零漂、再应用多邻点平均降噪的复合方法;利用噪声重构法建立的幅值判据可准确确定单个有效脉冲位置并实现相关数据截取.截得的Ⅰ型曲边梯形脉冲可近似为5参量等腰梯形函数,并可运用线性展开与梯度寻优相结合的最小二乘法拟合获得其特征参量,根据所得拟合结果可统计换算出速度、表面温度、直径及景深偏移等关键粒子状态参数.更多还原

【Abstract】 A newly established method was applied to the data processing of theoretically simulated signals and experimentally measured signals to evaluate its accuracy and applicability. A joint preprocessing method including null-shift elimination by low-pass filtering compensation and noise reduction by multiple neighboring points averaging is suggested, and a voltage criterion of the effective pulse based on the proposed noise reconstruction method was used to determine the position of the effective pulse and to extract the minimal measurement data concerning to the individual effective pulse. The type I trapezoid signal was approximately treated as an isosceles trapezoid and mathematically described by a piecewise function with 5 independent parameters. The least square fitting method combined with linear expansion and gradient-search algorithms was used to obtain the parameters of the piecewise function. The fitted results show that the (original) geometrical characteristics of the measured pulse are precisely outlined, therefore, the key parameters of in-flight particles, such as velocity, surface temperature, diameter, etc., are statistically calculated by the fitted parameters with acceptable accuracy. .更多还原