Shape parameter determination of double ellipsoid heat source model in numerical simulation of high energy beam welding;

Applying the principle of Step Acceleration Method(Pattern Search Method),two parameter values of double ellipsoid heat source model,the rear half of semi-axe Cr and the front half of semi-axe Cf,can be predicted by the combination of finite element numerical simulation and temperature measurement in X70 steel during multiple wires submerged arc welding.

During the simulation of multiple wires submerged arc welding, it is very important to define parameters of double ellipsoid source model, and these parameters can make a direct effect on the weld shape, however,it is very hard to get them through practical experiments.

On the basis of infrared measurementt,he temperature distribution on T-joints of 5A06 aluminum alloy cylinder structure was simulated by finite element method,developing a composite heat source constituted by Gauss heat source on the surface and inner double ellipsoid heat source.

A double ellipsoid heat source mode was adopted to depict the distribution of a moving GMAW.

Numerical simulation model for gas metal arc weding was developed,in which a double ellipsoid heat source mode was adopted and enthalpy of droplet was uniformly distributed over a special area of the molten pool.

The significance of sphere model and the limitation of O-QTM partition is discussed, and the significance of ellipsoid model in global-GIS is pointed out.