Turbulence: Numerical Analysis, Modeling, and Simulation

Turbulence: Numerical Analysis, Modeling, and Simulation

Analysis and modeling of buoyancy generated turbulence using numerical data

Rayleigh-Bernard convection offers a unique flow situation in which buoyancy-generated turbulence can be studied in isolation, free of the complicating influence of shear production of turbulence. The objective of this paper is to examine and model important aspects of buoyancy-generated turbulence using direct numerical simulation (DNS) data of Rayleigh-Bernard convection. In particular, we ex...

Direct numerical simulation of spiral turbulence

In this paper, we present results of three-dimensional direct numerical simulations of the spiral turbulence phenomenon in a range of moderate Reynolds numbers, in which alternating intertwined helical bands of turbulent and laminar fluids coexist and propagate between two counter-rotating concentric cylinders. We show that the turbulent spiral is comprised of numerous small-scale azimuthally e...

Large Scale Numerical Simulation for Superfluid Turbulence

Large scale numerical simulation of quantum turbulence is performed by using 3-D time-dependent Gross-Pitaevskii equation. The energy spectrum obeying Kolmogorov law and large scale self-similar structure of quantum vortex tangle are found in a fully developed dumped turbulent state. Width of the inertial range becomes large depending on the system size of the simulation that is consistent with...

Numerical Modeling of Saline Gravity Currents Using EARSM and Buoyant k- Turbulence Closures

Gravity currents are very common in nature and may appear in rivers, lakes, oceans, and the atmosphere. They are produced by the buoyant forces interacting between fluids of different densities and may introduce sediments and pollutants into water bodies. In this study, the hydrodynamics and propagation of gravity currents are investigated using WISE (Width Integrated Stratified Environments), ...