Direct numerical simulation of flapping flags in grid-induced turbulence

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...

Direct numerical simulation of passive scalar in decaying compressible turbulence

The passive scalars in the decaying compressible turbulence with the initial Reynolds number (defined by Taylor scale and RMS velocity) Re=72, the initial turbulent Mach numbers (defined by RMS velocity and mean sound speed) Mt=0.2-0.9, and the Schmidt numbers of passive scalar Sc=2-10 are numerically simulated by using a 7 order upwind difference scheme and 8 order group velocity control schem...

DIRECT NUMERICAL SIMULATION: A Tool in Turbulence Research

We review the direct numerical simulation (DNS) of turbulent flows. We stress that DNS is a research tool, and not a brute-force solution to the Navier-Stokes equations for engineering problems. The wide range of scales in turbulent flows requires that care be taken in their numerical solution. We discuss related numerical issues such as boundary conditions and spatial and temporal discretizati...

Direct Numerical Simulation of Wall Turbulence with Bubbles

Probing Physics of Magnetohydrodynamic Turbulence Using Direct Numerical Simulation

The energy spectrum and the nolinear cascade rates of MHD turbulence is not clearly understood. We have addressed this problem using direct numerical simulation and analytical calculations. Our numerical simulations indicate that Kolmogorov-like phenomenology with k energy spectrum, rather than Kraichnan’s k, appears to be applicable in MHD turbulence. Here, we also construct a self-consistent ...