Processing of Results From a Thermal Fem Analysis Using the Lock-in Method and Comparison With Experiment

Abstract

This article dealt with the comparison of results obtained from an experiment and from the numerical thermal FEM analysis. Sample with defects were printed on a 3D printer. A thermal wave from the halogen lamp to excite the front surface of the sample was used in the next step and the response was measured by a thermal camera. After processing the data in the software DisplayIMG, a phase image was created representing the 2D image of the material at a certain depth under the surface of the model. Lock-in method was applied to the results from the numerical thermal FEM analysis and the phase image was created. The programs code were created in MATLAB for a 4 points, multiple points and differential lockin method which were compared with the results from the experiment.

Nondestructive Evaluation of BSCC Artificial Heart Valves

“…Where S 0 is named the in-phase signal and S π 2 is usually named the amplitude signal. Both signals could be either positive or negative [14][15][16][17][18].…”

“…It is supposed to notice the whole process of excitation and then select the most suitable modulated frequency at which are detected damages on the measured subject. After detect the suitable modulated excitation frequency, resolution of radiation energy was succeeded drawn in the program like in phase and amplitude display [10][11][12][13][14].Furthermore, only the displays in phase were evaluated. In the first sample can be damage observed by the light area, with excitation frequency 0.03 Hz (Fig.…”