论文标题
Kraichnan模型和扩散混合的非平衡统计物理
The Kraichnan Model and Non-Equilibrium Statistical Physics of Diffusive Mixing
论文作者
论文摘要
我们讨论了从湍流对流的Kraichnan模型的方法应用于在高施密特数量下在液体混合物扩散期间引起的非平衡浓度波动的研究。这种方法可准确处理浓度波动的非线性对流，而无需线性化。值得注意的是，我们发现通过这种方法获得的静态和动态结构函数准确地重现了线性化波动流体动力学的预测。据认为，该协议是非命名异常化的类似物，但是不能保护高阶多点相关性。因此，后者应产生非变化的累积剂，这与线性化理论预测的高斯浓度波动不同。
We discuss application of methods from the Kraichnan model of turbulent advection to the study of non-equilibrium concentration fluctuations arising during diffusion in liquid mixtures at high Schmidt numbers. This approach treats nonlinear advection of concentration fluctuations exactly, without linearization. Remarkably, we find that static and dynamic structure functions obtained by this method reproduce precisely the predictions of linearized fluctuating hydrodynamics. It is argued that this agreement is an analogue of anomaly non-renormalization which does not, however, protect higher-order multi-point correlations. The latter should thus yield non-vanishing cumulants, unlike those for the Gaussian concentration fluctuations predicted by linearized theory.
