Numerical Studies on Heat Transfer and Fluid Flow during Laser Welding of Thin Sheet

Abstract:

Numerical simulation of heat transfer and fluid flow analysis of laser welding is essential to understand the physics of fluid motion, thermal cycles, heating and cooling rate and its effect on the formation of the final weld bead profile. The fusion geometry, weld thermal cycles, temperature and velocity field will vary depending on the welding process parameters. The influence of process parameters on the formation of weld bead geometry was analyzed in this study. In the simulation a plane Gaussian profile heat source was used to model the laser beam considering the equations of mass, momentum and energy. It was observed that due to the difference in surface tension coefficient the fluid moves from the central region of the molten pool to the outside. Increase in beam power or decrease in welding speed resulted in a high heating rate and less cooling rate due to high heat input. The simulated bead profiles were compared with the experimentally measured profile and was found to be in agreement.

• Periodical: Applied Mechanics and Materials (Volumes 592-594)
• Pages: 571-578
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.592-594.571
• Online since: July 2014
• Authors: K.R. Balasubramanian*, T. Suthakar, K. Sankaranarayanasamy, G. Buvanashekaran
• Keywords: Cooling Rate, Finite Volume Method (FVM), Fluid Flow, Laser Beam Welding, Thermal Cycle, Velocity Profiles

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