Influences of velocity on signal responses of magnetostatic non-destructive testing tools: a prediction from finite element analysis

A 2D finite element study of the influence of velocity on signal responses of electromagnetic non-destructive testing tools is presented in this paper. The Leismann-Frind method is applied to simulate the transient phenomenon of a magnetostatic probe inspection of a defective tube wall. A variable reluctance probe moving in a steel tube is considered. Simulated signal responses, received by sensors located at different points, when the probe passes a defect at different velocities are illustrated. The signals at different sensor positions have different physical phenomena governing them and essentially simulate different EM probe types. The information in these signals could possibly provide information invaluable for defect characterization