A complete mathematical description of oscillatory Couette flows within the framework of kinetic theory is not available in the literature. Motivated by this and their vast engineering applications, we present a parametric study of time-periodic oscillatory Couette flows using the unsteady direct simulation Monte Carlo ~DSMC! method. Computations are performed as a function of the Knudsen ~Kn! ...

We investigate the regime of fully developed homogeneous and isotropic turbulence of the Navier-Stokes (NS) equation in the presence of a stochastic forcing, using the nonperturbative (functional) renormalization group (NPRG). Within a simple approximation based on symmetries, we obtain the fixed-point solution of the NPRG flow equations that corresponds to fully developed turbulence both in d=...

In this study, we present experimental results on particle-wall collision in viscoelastic fluids. A sphere is released in a tank filled with poly(ethylene-oxide) (PEO) mixed with water with varying concentrations up to 1.5%. The effect of Stokes and Deborah numbers on the rebound velocity of a spherical particle colliding onto a wall is considered. It has been observed that the slope at which t...

in this paper, optimal distributed control of the time-dependent navier-stokes equations is considered. the control problem involves the minimization of a measure of the distance between the velocity field and a given target velocity field. a mixed numerical method involving a quasi-newton algorithm, a novel calculation of the gradients and an inhomogeneous navier-stokes solver, to find the opt...

In this work, particle-wall interaction in viscoelastic fluids is experimentally studied. The effect of Stokes number, Weissenberg number and surface roughness on the rebound velocity of a colliding spherical particle on a wall is considered. Different steel spherical particles are released in viscoelastic solutions of different high-molecular-weight polymers in water with different concentrati...

<abstract><p>This paper addresses the low Mach number limit for two-dimensional Navier–Stokes–Korteweg systems. The primary purpose is to investigate relevance of capillarity tensor analysis. For sake a concise exposition, our considerations focus on case quantum Navier-Stokes (QNS) equations. An outline subsequent generalization general viscosity and tensors provided. Our main resu...