Interaction models for mixtures with application to phase transitions

Continuum mixture theory formulates balances of mass, momentum and energy for a mixture body and non-material singular surfaces. An important component of these balances are the transfers that take place between constituents. These are described by volume interactions within a mixture body and surface interactions at a singular surface. The interactions sum to zero over all the constituents in order that there is no net production of mass, momentum or energy. The principle of Euclidean frame indifference is used to formulate the functional forms of these interactions. A simple set of volume and surface interaction functions are then postulated which satisfy the summation and frame indifference requirements. These partition the mass, momentum and energy transfers into a sum of the interactions between pairs of constituents. Illustrations are presented for a classical phase change front, a phase change front in a binary mixture and two examples of phase change in a tertiary mixture which demonstrate complex reabsorption processes. Copyright © 1996 Elsevier Science Ltd.