Abstract: A series of strategies based on the principle of knock detection are proposed, and guidance is given to the detection process, to address the problems of low accuracy, poor efficiency, confusion, and disorder in the knock detection of the double-base propellant/coating interface debonding. Based on the basic characteristics of knock detection, two specific curved surfaces of the tested cylinder and ball head are meshed independently, and the possible accuracy and sensitivity problems in meshing are experimentally evaluated. A mathematical model of the detection efficiency of the double-based propellant/coating interface is constructed using Barlow's assessment approach as a starting point. The model quantifies the sequential detection time cost and periodic detection interval. And a box-plot based fluctuation range detection approach is proposed to visualize defect location and severity in a defect cloud map. The proposed method is of guiding significance for the knock detection test procedure and post-test treatment measures, according to the whole process flow and experiment analysis of cases.

Key words: tapdetection, meshing, areaaccuracy, testingefficiencystrategies, box-plot