论文部分内容阅读
焊接温度场的数值计算,近年来取得不少进展,但其中大多是采用线性有限单元方程或差分方程求解的。本文对非线性的热传导问题进行了有限元分析,建立了焊接温度场的计算模型,编制了相应的计算机程序。该程序考虑了材料热物理性能随温度的变化以及表面的散热情况,并可以进行固定热源或移动热源、薄板或厚板、准稳态或非准稳态二维温度场的有限元分析。文中就固定热源或移动热源薄板对接焊等几个具体实例进行了有限元分析。结果表明,考虑热物理性能随温度的变化以及表面的散热条件能使计算精度得到提高。并且还表明,只要选取合适的计算模型尺寸,焊缝及近缝区的温度分布便可趋向于准稳定状态。
In recent years, much progress has been made in numerical calculation of welding temperature field, but most of them are solved by linear finite element equations or difference equations. In this paper, the finite element analysis of nonlinear heat conduction problems is established, the calculation model of welding temperature field is established, and the corresponding computer program is compiled. The program takes into account the change of the thermophysical properties of the material with temperature and the surface heat dissipation, and can carry out the finite element analysis of two-dimensional temperature field of fixed heat source or moving heat source, sheet or plate, quasi-steady state or non-quasi-steady state. In this paper, finite element analysis is carried out on several specific examples such as fixed heat source or movable heat source plate butt welding. The results show that the calculation accuracy can be improved by considering the changes of the thermophysical properties with temperature and the surface heat dissipation conditions. It is also shown that the temperature distribution in the weld and near-seam zone tends to be quasi-stable as long as the appropriate calculation model is chosen.