Heat Transfer Modelling in Wide Gap Rail Thermite Welding

In the current study, a thermal model was used to investigate the effects of welding parameters on the distribution of temperature in wide gap aluminothermic rail welds. To solve the governing thermal equation, SUTCAST, a finite difference program (FDM) was employed while different aspects such as phase change and convective heat transfer in weld pool were taken into account in the numerical solution. To validate the predictions, the modeling results were compared with the experiments and despite some utilized simplifications, a reasonable agreement was found between numerical and experimental results. The effects of welding variables such as preheating; initial liquid temperature and weld gap on temperature distribution were studied. The results of the modeling showed that the magnitude of weld gap had the greatest influence on thermal behavior of the joint and the highest weld gap results in most stable results.