Methods motivated by non-equilibrium statistical mechanics of turbulence are applied to solve an important practical problem in geophysical fluid dynamics, namely the parametrization of subgrid-scale eddies needed in large-eddy simulations (LESs). A direct stochastic modelling scheme that is closely related to techniques based on statistical closure theories, but which is more generally applica...

We aim at giving support to the idea that no physical Large Eddy Simulation (LES) model should be used in the simulation of turbulent flows. It is heuristically shown that the rate of transfer of subgrid kinetic energy provided by the stabilization terms of the Orthogonal Subgrid Scale (OSS) finite element method is already proportional to the molecular physical dissipation rate (for an appropr...

A new class of subgrid closures for large eddy simulation (LES) of turbulence is developed, based on the construction of synthetic, fractal subgrid-scale fields. The relevant mathematical tool, fractal interpolation, allows to interpolate the resolved velocity with fields that have fluctuations down to much smaller scales and to compute the required stresses explicitly. In one dimension, the ap...

This work studies the momentum and energy transport mechanisms in the corner between a free surface and a solid wall. We perform large-eddy simulations of the incompressible fully developed turbulent flow in a square duct bounded above by a free-slip wall, for Reynolds numbers based on the mean friction velocity and the duct width equal to 360, 600 and 1000. The flow in the corner is strongly a...

The velocity and concentration fields in a liquid-phase confined planar-jet reactor were measured using particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF). Measurements were taken at downstream distances from the jet splitter plates of 0, 1, 4.5, 7.5, 12, and 15 jet widths for a Reynolds number of 50,000 based on the distance between two sidewalls of the test section....

Realizing the internal flow visualization inside the drip irrigation emitter is the basis of optimizing the labyrinth path structure and promoting its anti-clogging capability. The Computational FluidDynamics (CFD)method has become an effective approach to research the water movement in the labyrinth path of the drip irrigation emitter. In this paper, the standard k-ε model and the Large Eddy S...

This paper presents an optimized low-dissipation monotonicity-preserving (MPLD) scheme for numerical simulations of high-speed turbulent flows with shock waves. By using the bandwidth dissipation optimization method (BDOM), the linear dissipation of the original MP scheme of Suresh and Huynh (J. Comput. Phys. 136, 83–99, 1997) is significantly reduced in the newly developed MP-LD scheme. Meanwh...

As one of the most promising propulsive systems in the future, the scramjet engine has drawn the attention of many researchers. The two-dimensional coupled implicit NS equations, the standard k-ε turbulence model and the finite-rate/eddy-dissipation reaction model have been applied to numerically simulate the flow field of the hydrogen fueled scramjet combustor with a cavity flameholder under t...

The ocean circulation is a cause and consequence of fluid scale interactions from millimeters to 10,000km. Although the wind field produces a large energy input to the ocean, all but about 10% appears to be dissipated within about 100m of the sea surface, rendering very difficult observations of the energy divergence necessary to maintain the full water column flow. Attention thus shifts to the...