三维阶谱有限元法在倒虹吸工程温度场中的应用研究

引入了阶谱单元基函数，对非稳定温度场的有限元算法进行了改进，给出了确定虚结点的温度初值和边界值的方法，编制了相应的计算程序，并应用于某大型倒虹吸工程的混凝土施工仿真计算。与常规有限元方法的对比结果表明，在网格稀疏的情况下，阶谱有限元法计算的特征点温度历时曲线和温度场等值线与准确值吻合得较好，而常规有限元法则误差相对较大，采用阶谱有限元法对大体积混凝土结构进行非稳定温度场计算，可以在保证计算精度的前提下减少单元数量，从而明显降低前处理和计算的时间成本。

Application of three_dimensional hierarchical FEM to calculation of temperaturefield in concrete inverted siphon engineering

The hierarchical element basis function is introduced into the finite element algorithm to improve the FEM calculation of unsteady temperature field. The way to adopt the temperature initial value and boundary value of virtual node is given. The corresponding computation program for simulating the temperature field of a large_scale inverted siphon engineering is developed. At the same time the FEM analysis by using the traditional method is carried out. The comparison of the calculation results of these two methods shows that, under the condition of the same computational precision, the element number can be reduced if the hierarchical element method is adopted, so that the time consumption for pre_process and computation is obviously reduced.