Micromorphic balance equations in mass transport and mass production

The balance equations for micromorphic materials with mass flux and mass production are determined based on the phenomenon of self-diffusion. In this study, the self-diffusive flux is the flux of mass of a single micromorphic species within itself which is captured by defining the relative macro-element spatial velocity vector and the relative micro-gyration tensor. By use of a binary micromorphic mixture theory, the self-diffusion of a single micromorphic species within itself results in an extra diffusive momentum field, an extra diffusive moment of momentum and their respective non-compliant terms. The concepts of the macro- and micro-mass flux are studied in the framework of the micromorphic theory. Furthermore, based on the Clausius-Duhem principle, admissible constitutive equations are presented for the diffusive and non-compliant quantities. (C) 2020 Elsevier Ltd. All rights reserved.