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Dislocation Dynamics in Rayleigh-Bénard Convection

Th. Walter·W. Pesch·E. Bodenschatz
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Abstract

Theoretical results on the dynamics of dislocations in Rayleigh-Bénard convection are reported both for Swift-Hohenberg models and the Boussinesq equations. For intermediate Prandtl numbers the motion of dislocations is found to be driven by the superposition of two independent contributions: (i) the Peach-Koehler force derived from the change of a Lyapunov potential with pattern wave number; (ii) a non-potential advection force on the dislocation core by its self-generated mean flow. Their competition allows for the first time to understand the experimentally observed bound dislocation pairs.

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Th. Walter, W. Pesch, E. Bodenschatz. 2002-12-23. Dislocation Dynamics in Rayleigh-Bénard Convection. https://arxiv.org/abs/cond-mat/0212570

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