境界要素法による熱弾塑性応力解析について

抄録

The boundary integral formulation of the two-dimensional thermoelastoplasticity problem is presented employing linear interpolation functions for boundary elements as well as for internal cells. The semi-analytical approach proposed by Telles and Brebbia is utilized to derive derivatives of the singular integral and to compute its principal values. It is shown that stresses on the boundary can be easily evaluated by applying the Duhamel-Neumann analogy. Some numerical calculations are made to the specific problem of centrally heated disk using two types of interior cell discretization. The boundary element solutions of the thermoelastic analysis agree well with the analytical solutions even if the coarse mesh type is used. In the thermoelastoplastic analysis, three different values of equivalent plastic strain increments are used as the prescribed convergence criterion during iterative process. Then, the accuracy of the calculated results and CPU-times are compared. In order to obtain reasonable results of displacements, strains and stresses, it is concluded that the use of relatively fine mesh of interior cell discretization especially in plastically deformed region is more preferable than precise evaluation of the plastic strain increments at each nodal points during the iterative process.