An emergent property of decaying two-dimensional turbulence is shown to be a weak but persistent statistical heating, or tendency towards clustering of like-signed vortices. The rate of this heating, which is driven by changes to the vortex population due to vortex mergers and straining events, provides a strong constraint on both vortex decay laws and kinetic theories of vortex interactions. A quasi-equilibrium statistical theory determines the energy spectrum from just the vortex interaction energy and bulk information about the number density of the vortices. The emergent heating rate is shown to determine the upscale transfer of energy, and is a powerful constraint on power law descriptions of the evolving vortex population.

中文翻译：

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衰减的二维湍流经历统计加热

衰减的二维湍流的涌现特性显示为微弱但持续的统计加热，或趋向于聚集类似符号的涡流。这种加热的速度是由于涡旋合并和应变事件而引起的涡旋总数的变化所驱动的，这对涡旋衰减定律和涡旋相互作用的动力学理论都提供了强大的约束。准平衡统计理论仅根据涡旋相互作用能和有关旋涡数密度的整体信息确定能谱。显示出的升温速率决定了能量的高档转移，并且是对不断发展的涡流种群的幂律描述的有力约束。