采用超声波对旋压固体火箭发动机的绝热层厚度进行检测时, 检测信号中的纹理噪声影响了界面回波的确定, 进而影响绝热层厚度的准确测量。通过分析绝热层超声测厚信号特点和噪声来源, 提出了利用小波变换对检测信号进行处理的方法。仿真结果表明, 运用小波分析得到的厚度特征有很大的改善, 通过试件厚度的计算, 验证了测量的有效性和准确性。

During the ultrasonic thickness detection for the heat insulation layer of spinning-made solid rocket motors, the texture noises in the echo signals affected the determination of the interface returning wave and the accuracy of the thickness measurement. By analyzing the characteristics of ultrasonic thickness signals and the sources of the noises, a processing scheme using a wavelet analyzing post-processing program was proposed. Simulation results were presented to verify the validity and the accuracy of the measurement.