Dislocation motion : a wavenumber selection mechanism in Rayleigh-Benard convection
نویسندگان
چکیده
2014 In this article, we report the measurement and analysis of the climbing velocity of an isolated dislocation in a Rayleigh-Bénard roll structure of large extension, as a function of the wavenumber and of the Rayleigh number. The motion of this dislocation in the otherwise regular structure is found to be a wavenumber selection mechanism. Further, we compare this mechanism with that provided by grain boundary defects. Both mechanisms lead to a wavenumber selection consisting of a unique wavevector rather than a band, which allows the selection curve to be accurately determined. J. Physique 45 (1984) 35-48 JANVIER 1984, 1
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