高能束焊接双椭球热源模型参数的确定

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

双椭球热源模型常用于高能束焊接过程数值模拟 ,模型中形状参数选择的合理与否对于计算精度和效率有很大影响。由于缺乏定量化描述 ,进行数值模拟时 ,只能依靠经验通过反复试算确定模型参数 ,选择的随机性很大。为此该文提出了一种用解析法计算高能束焊接双椭球热源模型参数的方法 ,通过实例计算和有限元模拟对该方法进行了验证 ,并建立了确定模型形状参数的经验公式。研究结果表明 ,使用该方法只需进行简单的解析计算便可直接求得数值模拟所需的热源参数 ,简化了试算过程 ,提高了数值模拟的效率和精度。

Double ellipsoid heat source model is often used in numerical simulation of high energy beam welding.The precision and efficiency of computation are greatly influenced by the shape parameters of model.Due to lack of quantitative formula,the shape parameters have to be obtained by repeating tentative calculations by experience before.And the tentative calculation is affected by random factors to a great extent.Therefore an algorithm is presented so that the shape parameters can be calculated by empiric formula,also the algorithm is verified as valid by FEM computation.It indicates that parameters needed in simulation can be easily obtained by simple analytical calculation.By using this algorithm,the tentative calculations can be omitted,and the efficiency and precision of computation can be improved greatly.