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arXiv · 2402.16762

The influence of the vorticity-scalar correlation on mixing

Xi-Yuan Yin·Wesley Agoua·Tong Wu·Wouter J. T. Bos
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Abstract

We investigate the role of the correlation between a scalar quantity and the vorticity in two-dimensional mixing at infinite P\'eclet number. We assess, using a diffusivity independent mixing-norm, the dynamics of both Galerkin-truncated ensembles and freely evolving two-dimensional scalar mixing. Both statistical mechanics and numerical experiments show how the mixing-rate is attenuated when vorticity and scalar are initially correlated. Since the vorticity is shown to be a poorly mixing scalar, the results suggest that, in general, mixing can be enhanced by minimizing the correlation between vorticity and passive scalar.

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Xi-Yuan Yin, Wesley Agoua, Tong Wu, Wouter J. T. Bos. 2024-02-26. The influence of the vorticity-scalar correlation on mixing. https://arxiv.org/abs/2402.16762

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