熱応力解析

It's a coupled analysis of thermal strain and thermal stress arising from temperature distribution. Stress occurs under constrained conditions. Essential for structures with large temperature gradients like engine components and turbine disks.

We use spatial discretization by the Finite Element Method (FEM). We assemble the element stiffness matrix and construct the global stiffness equation.

We perform a transformation to the weak form (variational form) and use Galerkin method formulation with test functions and shape functions. The choice of element type (low-order elements vs. higher-order elements, full integration vs. reduced integration) directly affects the trade-off between solution accuracy and computational cost.

Solve the simultaneous equations using direct methods (LU decomposition, Cholesky decomposition) or iterative methods (CG method, GMRES method). Preconditioned iterative methods are effective for large-scale problems.

Founded in Sweden in 1986. Started as FEMLAB with MATLAB integration, later renamed to COMSOL. Strong in multiphysics.

Developed in 1970 by Swanson Analysis Systems Inc. (SASI). APDL (Ansys Parametric Design Language) based.

Developed in 1978 by HKS (Hibbitt, Karlsson & Sorensen). Acquired by Dassault Systèmes in 2005 and integrated into the SIMULIA brand.

When converting models between different solvers, attention is needed regarding the correspondence of element types, compatibility of material models, and differences in the representation of loads/boundary conditions. Especially, higher-order elements and special elements (cohesive elements, user-defined elements, etc.) often cannot be directly converted between solvers.