Numerical Analysis of a Coaxial Impingement Jet and Application for a Laser Welding of AZ91 Magnesium Alloy with Shielding Gas

摘要

A coaxial jet impinging a vertical heated plate is numerically investigated using the Fluent CFD code. The best numerical simulations are carried out using the k-ω SST turbulence model with considered assumptions. Results obtained by the developed numerical model have enabled to determine essentially the average Nu numbers relating to certain Reynolds number for H/D=4 position of the heated plate. A comparison of the accuracy of different turbulent models is proposed in this study. Comparisons with a single jet and with a horizontal disposition are also proposed. Subsequently, an industrial application is proposed;the laser welding process. For that, a moving distributed heat source model has been implemented in order to predict temperature distributions through the welding process of a magnesium alloy with the gas shielding.