基于局部网格细化的泵头体强度有限元分析

Local Mesh Refinement-based Finite Element Analysis of Pump Head Strength

泵头体内部形状复杂,难以用材料力学公式得到应力的解析解。为此,对某三缸压裂泵泵头体强度进行有限元分析。在取对称模型的条件下,发现多处应力集中位置。各处应力最大值较接近,在结构改进时需全盘考虑。为保证应力分析精度,提出一种局部网格细化的方法,在网格节点数不超出计算机内存限制的情况下,该方法以迭代计算的方式减小网格尺寸。计算结果表明,该网格细化方法可有效提高应力集中处的应力计算精度。采用Python和VB开发了通用性较好的网格细化及流程控制程序,该程序也可用于解决其他有限元分析中出现的应力集中问题。

The internal form of pump head is so complex that it is difficult to use the mechanical formula to obtain the analytic solution. Therefore, the finite element analysis of the strength of some three-cylinder fracture pump head was conducted. Quite a few positions of stress concentration were found with the symmetrical model as the con- dition. The maximum values of stress at the positions are close to each other, which should be considered compre- hensively in structural improvement. To ensure the precision of stress analysis, the method of local mesh refinement was formulated. Under the condition that the number of mesh nodes is within the constraint of computer memory, the method reduced the mesh size through iterative computation. The calculation shows that the method of mesh refinement can effectively improve the stress calculation precision at stress concentration positions. The Python and VB were adopted to develop the program of mesh refinement and process control with desirable universality. The program can be applied to deal with stress concentration in other finite element analyses.