A hybrid flux axisymmetric model for thermal analysis

A hybrid method for heat conduction analysis in axisymmetric bodies is presented. The variational support is a two-field functional which includes heat flux and temperature as independent variables. The heat flux is assumed to satisfy the inner thermal balance equations and the temperature is defined on the body boundary. From this formulation a finite element model is developed, where the temperature on the element boundary is employed to relax the heat flux continuity at the interelement. The stability conditions for the proposed approach are discussed in detail as well as the invariance requirements, and a guideline to properly select the equilibrating flux fields is given. The numerical tests show the good overall accuracy of the hybrid model and its limited sensitivity to element geometry distortions. These features make the proposed approach reliable for both thermal and thermostructural analysis.