Direct control of the small-scale energy balance in two-dimensional fluid dynamics

作者：Frank Jason; Leimkuhler Benedict; Myerscough Keith W^*

来源：Journal of Fluid Mechanics, 2015, 782: 240-259.

DOI：10.1017/jfm.2015.526

• atmospheric flows
• computational methods
• homogeneous turbulence

We explore the direct modification of the pseudo-spectral truncation of two-dimensional, incompressible fluid dynamics to maintain a prescribed kinetic energy spectrum. The method provides a means of simulating fluid states with defined spectral properties, for the purpose of matching simulation statistics to given information, arising from observations, theoretical prediction or high-fidelity simulation. In the scheme outlined here, Nose Hoover thermostats, commonly used in molecular dynamics, are introduced as feedback controls applied to energy shells of the Fourier-discretized Navier Stokes equations. As we demonstrate in numerical experiments, the dynamical properties (quantified using autocorrelation functions) are only modestly perturbed by our device, while ensemble dispersion is significantly enhanced compared with simulations of a corresponding truncation incorporating hyperviscosity.

• 出版日期2015-11