Direct numerical simulation of axisymmetric 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 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 ...

Direct Numerical Simulation of Turbulence Using Divergence-Free Wavelets

We present a numerical method based on divergence-free wavelets to solve the incompressible Navier-Stokes equations. We introduce a new scheme which uses anisotropic (or generalized) divergence-free wavelets, and which only needs Fast Wavelet Transform algorithms. We prove its stability and show convincing numerical experiments.

Direct numerical simulation of turbulence using GPU accelerated supercomputers

Direct numerical simulations of turbulence are optimized for up to 192 graphics processors. The results from two large GPU clusters are compared to the performance of corresponding CPU clusters. A number of important algorithm changes are necessary to access the full computational power of graphics processors and these adaptations are discussed. It is shown that the handling of subdomain commun...