Keyhole formation and collapse in plasma arc welding
نویسندگان
چکیده
A mathematical model is developed to describe the heat transfer and fluid flow in stationary keyhole plasma arc welding. Using the volume of fluid method, the processes of heating, melting, collapsing and subsequent solidifying in the molten pool are dynamically studied. The predicted results have been compared with the experimental weld and keyhole shape. Using the LaserStrobe video system, the captured images of the upper surface of the weld pool are used to verify the predicted transient development of the weld pool. It is indicated that theoretical predictions and the experimental results are in close agreement.
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