Thermographic Inspection Simulation of One Kind of Rail Defects

Abstract

Rail is an important foundation of rail transit, and defects on the rail may pose a serious threat to rail transit. As a new non-destructive testing method, thermographic detection shows an excellent application prospect. In order to verify whether thermographic detection technology can be used to detect the defects on the rail, especially the defects at the bottom of the rail. The ANSYS software is used to model the rails under different conditions, and the heat flow simulation experiment is carried out to obtain the temperature change results when the heat flow passes through the defects and when it does not. The existence and location of defects can be determined by observing how the heat flow changes due to the existence of defects.Although the results show that surface fracture defects and defects towards the bottom edge of the rail can be clearly detected by thermal modeling under laser heating conditions, for transverse cracks that exist near the center of the rail bottom, the simulation experiments still cannot distinguish the temperature differences at the same observation location under current parameters. So it may be necessary to further optimize the experimental process, or increase the experimental parameters, so that the thermal modeling method can be better applied for non-destructive testing of rail defects.