A practical flow diagram for the solution of complex non-linear thermo-mechanical numerical models

Abstract In this paper the authors propose a practical flow diagram for the systematic development and solution of complex thermo-mechanical finite element analysis models. The proposed diagram consists of three different phases and provides a step-by-step guide for the development of the final thermo-mechanical model, taking into account convergence issues, mesh density and estimation of time step magnitude. In phase I, a preliminary thermo-mechanical analysis is carried out in order to get an idea of the model behaviour, the required resources and the feasibility of the overall analysis. In phase II the final thermal model is developed in full, taking into account the mechanical results obtained at the end of phase I, whereas in phase III the final mechanical model is generated on the basis of a continuously modified thermal model. The proposed procedure presented herein in the form of a flow diagram provides the capability for gradual output of the numerical results (preliminary results, thermal results, mechanical results), while paying attention to the time-consuming problem of results convergence required for a numerically accurate analysis. The former is an important issue for large-scale complex simulation projects, whereas the latter provides evidence that the development of the numerical model has been realized on the basis of the modelling laws. For better presentation and understanding, the proposed procedure is applied to the study of a finite element analysis thermo-mechanical model, where increased intricacy generally exists.

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