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arXiv · 1911.11315

Nonuniversal transition to condensate formation in two-dimensional turbulence

Moritz Linkmann·Manuel Hohmann·Bruno Eckhardt
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Abstract

The occurrence of system-scale coherent structures, so-called condensates, is a well-known phenomenon in two-dimensional turbulence. Here, the transition to condensate formation is investigated as a function of the magnitude of the force and for different types of forcing. Random forces with constant mean energy input lead to a supercritical transition, while forcing through a small-scale linear instability results in a subcritical transition with bistability and hysteresis. That is, the transition to condensate formation in two-dimensional turbulence is nonuniversal. For the supercritical case we quantify the effect of large-scale friction on the value of the critical exponent and the location of the critical point.

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Moritz Linkmann, Manuel Hohmann, Bruno Eckhardt. 2019-11-26. Nonuniversal transition to condensate formation in two-dimensional turbulence. https://doi.org/10.1017/jfm.2020.198

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