Direct numerical simulation of supercritical annular electroconvection

Annular electroconvection with shear

We report experiments on convection driven by a radial electrical force in suspended annular smectic A liquid crystal films. In the absence of an externally imposed azimuthal shear, a stationary one-dimensional (1D) pattern consisting of symmetric vortex pairs is formed via a supercritical transition at the onset of convection. Shearing reduces the symmetries of the base state and produces a tr...

numerical simulation of shock waves structure in an annular channel

in this work, the feasibility study for design of a laboratory sample rde which has an annular geometry with diameter of 76 mm and length of 101 mm has been performed. detonation engines are expected to be used as propulsion system in aerospace applications in the future. several types of detonation engines are currently under examination, including the rotating detonation engine (rde). first, ...

Direct Numerical Simulation of vortices

Temporally regularized direct numerical simulation

Experience with fluid-flow simulation suggests that, in some instances, under-resolved direct numerical simulation (DNS), without a residual-stress model per se but with artificial damping of small scales to account for energy lost in the cascade from resolved to unresolved scales, may be as reliable as simulations based on more complex models of turbulence. One efficient and versatile manner t...

Absolute Permeability Calculation by Direct Numerical Simulation in Porous Media

Simulating fluid flow at micro level is an ongoing problem. Simplified macroscopic flow models like Darcy’s law is unable to estimate fluid dynamic properties of porous media. The digital sample reconstruction by high resolution X-ray computed tomography scanning and fluid-dynamics simulation, together with the increasing power of super-computers, allow to carry out pore-scale simulations throu...