Consistent thermal stress calculation by using a new approach of the enhanced assumed strain method Original Research Article

A three-field hybrid functional with displacement, strain and stress assumptions has been proposed. By introducing the enhanced assumed strain concept to the proposed functional, a more general finite element formulation for the enhanced assumed strain method has been derived. Unlike the previous version of the enhanced assumed strain method, the stresses can be evaluated from variational formulation within variational framework. The present formulation has been applied to the thermal stress problems and it has been addressed that, by suitable assumption of the enhanced assumed strains, the spurious oscillation of the thermal stresses can be successfully overcome. The process of designing the interpolation functions of the enhanced strains which guarantee the field-consistency of the strain field, is rational and systematic.