Analytical Modeling of Residual Stress in Railroad Rails Using Critically Refracted Longitudinal Ultrasonic Waves With COMSOL Multiphysics Module Available to Purchase

Assessment of residual stresses in railroad rails without destructing the material plays a vital role in rail road safety. Ultrasonic testing is a commonly used nondestructive technique to determine the stresses in any structure. Ultrasonic stress evaluation technique is based on acoustoelastic effect which refers to the changes in the speed of the elastic wave propagation in a structure undergoing static elastic deformations. Critically refracted longitudinal (L_CR) waves can be used as the propagating waves because it is a bulk wave and can reflect the surface and subsurface characteristics by the wave property linked to material elasticity. In this paper, a COMSOL Multiphysics module-based Finite Element Method (FEM) model is developed and numerical simulations are carried out for critically refracted longitudinal wave propagation in a railroad rail head for residual stresses. The time travel data results from this FEM Model are validated with reported experimental results.