C.S. Wu
,
J.Q. Gao
金属学报(英文版)
The anode region of welding arc is divided into three subzones: the anode boundary layer, the presheath and the sheath. A model is established for analyzing the transport mechanisms in the anode boundary layer. The computer program is designed and the governing equations of the dominating processes with the boundary conditions taken from the solutions of LTE plasmas are solved by applying the Runge-Kutta procedure.One parameter θ, the ratio of the heavy particle temperature at the free-fall edge to the anode surface temperature, is introduced into this study. The results indicate that when the parameter θ is of the value 6 the predicted heat flux at the anode surface matches the measured one. Based on the model, various plasma properties in the boundary layer can be obtained. The calculated results are in good agreement with the measurements.
关键词:
welding arc
,
null
,
null
J.S. Sun
,
J.Q. Gao
,
Y. Feng
,
Y.W. Luan
金属学报(英文版)
A mathematical model describing the behavior of metal inert gas (MIG) welding is
formulated in the paper. By means of numerical simulation, the influence of surface-active elements on fluid flow of MIG weldpool is studied. The calculation results
show that by adding surface-active elements, the fluid flow behavior is drastically
changed and the flow fluid flows from lower to upper in vertical direction at the rear
of weldpool (w>0). The physical phenomenon is explained from the viewpoint of fluid
flow behavior of weldpool that the properties of weld metal is greatly improved and
the content of diffused hydrogen is reduced, thus providing a basis for developing new
welding materials.
关键词:
surface-active elements
,
null
,
null