Preprint 35/2006

Normal modes and nonlinear stability behaviour of dynamic phase boundaries in elastic materials

Heinrich Freistühler and Ramón G. Plaza

Contact the author: Please use for correspondence this email.
Submission date: 29. Mar. 2006
Pages: 23
published in: Archive for rational mechanics and analysis, 186 (2007) 1, p. 1-24 
DOI number (of the published article): 10.1007/s00205-007-0051-y
Keywords and phrases: phase boundaries, Lopatinski determinant
Download full preprint: PDF (288 kB), PS ziped (269 kB)

This paper considers an ideal non-thermal elastic medium described by a stored-energy function W. It studies time-dependent configurations with subsonically moving phase boundaries across which, in addition to the jump relations (of Rankine-Hugoniot type) expressing conservation, some kinetic rule g acts as a two-sided boundary condition. The paper establishes a concise version of a normal-modes determinant that characterizes the local-in-time linear and nonlinear (in)stability of such patterns. Specific attention is given to the case where W has two local minimizers formula9 which can coexist via a static planar phase boundary. Dynamic perturbations of such configurations being of particular interest, the paper shows that the stability behaviour of corresponding almost-static phase boundaries is uniformly controlled by an explicit expression that can be determined from derivatives of W and g at formula15 and formula17.

23.06.2018, 02:11