NUMERICAL MODELING OF CONVECTION-DIFFUSION PHASE-CHANGE PROBLEMS

A numerical methodology is presented for the modeling of convection-di ffusion controlled mushy region change problems. An efficient and accu rate non-staggered control volume method, based on the momentum interp olation practice and on a high-order convection differencing scheme, i s proposed for the solution of the continuum model equation. Suitable numerical techniques are implemented to overcome the numerical instabi lity problems resulting from the strong coupling between the equations of the model. Special attention is given on the efficient treatment o f the latent head evolution in the energy equation. A new numerical te chnique is developed which accounts for the dependence of the latent h eat on the variation of temperature and concentration fields. The prop osed method is applied on two phase change problems. Satisfactory agre ement with previously published results is observed.