Reduced relative entropy techniques for a priori analysis of multiphase problems in elastodynamics

Giesselmann, J. and Pryer, T. (2016) Reduced relative entropy techniques for a priori analysis of multiphase problems in elastodynamics. BIT Numerical Mathematics, 56 (1). pp. 99-127. ISSN 1572-9125 doi: 10.1007/s10543-015-0560-2

Abstract/Summary

We give an a priori analysis of a semi-discrete discontinuous Galerkin scheme approximating solutions to a model of multiphase elastodynamics which involves an energy density depending not only on the strain but also the strain gradient. A key component in the analysis is the reduced relative entropy stability framework developed in Giesselmann (SIAM J Math Anal 46(5):3518–3539, 2014). The estimate we derive is optimal in the L∞(0,T;dG) norm for the strain and the L2(0,T;dG) norm for the velocity, where dG is an appropriate mesh dependent H1-like space.