Numerical Simulation And Analysis Of Lock-in Thermography Based On ANSYS For NDT

In recent years, the lock-in thermography technology has been increasingly used in NDT for surface defects. Lock-in thermography uses thermal imaging to detect objects Infrared heat wave of the surface, which creates thermal image map, thermal map showing local heat wave phase and amplitude changes. The heat wave contact surface of the material is sensitive to the contact surface of the material. Lock-in thermal imaging is used for detecting surface defects to determine material properties, coating thickness measurement. It is a common non-destructive evaluation (NDE) technology. In particular, Lock-in thermography is more suitable to detect composite material structure.To better carry out lock-in infrared NDT, it must totally understand the lock-in process of heating objects on the surface to change the internal structure of the phase, to be more precise infrared NDT parameters setting. Compared with pulsed infrared NDT, the lock-in infrared quantitative studies have to be further improved. Lock-in nondestructive testing, calibration using most of the existing quantitative manner, but because of the seized samples and the diversity of defects, there are certain limitations to identify only by experiment, some pre-implantation defects using sample testing parameters identified is possible. But for the majority of cases, such as delimitation and the gap defect are very difficult to imitate. So it is very difficult to determine the optimum parameters through experiment. This requires the use of theoretical models or numerical model testing to determine the optimum parameters for the development of accurate and reliable testing standards provide the basis, and therefore requires a theoretical model of effective surface structure reconstruction to determine the correct ways and means of simulation.Based on the finite element method, it uses large-scale finite element analysis software ANSYS to simulate lock-heating infrared NDT process, the impact of phase-locking infrared heating nondestructive testing of a number of factors, and several different types of defects are given by the finite element simulation methods. It uses MATLAB to process the follow-up data, obtained by the information and the corresponding data processing. Finally, France CEDIP Infrared Imaging System for experimental verification results shows that the use of lock-in infrared finite element simulation of nondestructive testing is feasible. This method can be used to lock-in infrared NDT on the mechanism to predict structure more complex, more types of defects specimen test results, optimization of process parameters to achieve the best detection results. In the end, this paper put forward the use of finite the appropriate mathematical model simulation defects accurate and efficient data processing method is still lock-in infrared NDT numerical simulation focus to simulate the process of lock-in thermography by finite element method.