Modeling of multi-component flows with phase transition and application to collapsing bubbles∗
نویسندگان
چکیده
The classical two-phase flow model of Baer and Nunziato is generalized to a thermody-namic consistent multi-component model in multi dimensions. The extended model allowsto deal with phase transitions where exchange processes are modeled by relaxation terms.In particular, chemical relaxation is based on chemical potentials instead of Gibbs freeenergies. New procedures to determine the equilibrium state are derived that in combi-nation with local grid refinement significantly reduce the computational effort and allowfor multi-dimensional computations also for more than two components. Artificial param-eters in the model as well as numerical threshold values frequently introduced to stabilizethe computation are not needed for the extended model. Stability and efficiency of themodel and the implementation is verified by means of a spherical symmetric collapse ofa laser induced cavitation bubble as well as two-dimensional shock bubble interaction forthree-component fluid, where thermal relaxation is performed in the entire flow field.
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