We numerically demonstrate a stable mechanical suspension of a silica cylinder within a metallic cylinder separated by ethanol, via a repulsive Casimir force between the silica and the metal. We investigate cylinders with both circular and square cross sections, and show that the latter exhibit a stable orientation as well as a stable position, via a method to compute Casimir torques for finite...

Three-dimensional (3D) superflows past a circular cylinder are studied by numerically integrating the nonlinear Schrodinger equation. 3D initial data are built from the two-dimensional (2D) stationary vortex nucleation solutions. Quasistationary half-ring vortices, pinned at the sides of the cylinder, are generated after a short time. On a longer time scale, either 3D vortex stretching induces ...

In this study, the aerodynamic sound generated from the inclined circular cylinder was investigated experimentally and numerically. The generated sound and a coherent length of velocity fluctuation along the cylinder axis were measured by a low-noise wind tunnel with endplates. The sound and the flow in wake were also simulated by Large Eddy Simulation and Lighthill-Curle’s equation. We got the...

Analytical solutions corresponding to the starting flow of an Oldroyd-B fluid between rotating cylinders are established. If the radius of the inner cylinder tends to zero the flow within a circular cylinder is obtained. The well-known solutions for a Navier-Stokes fluid, as well as those corresponding to a Maxwell fluid and to a second grade one, appear as limiting cases of our solutions. The ...

A direct forcing method for the simulation of particulate flows based on immersed boundary-lattice Boltzmann method is used to study the flow of powerlaw fluid through an infinite array of circular cylinders with cylinder separations of 20a (a is the cylinder radius) with laminar shedding behind cylinders. Time averaged drag coefficient, maximum of lift coefficient and Strouhal number are given...

Direct numerical simulation results of aeolian tones generated by a two-dimensional obstacle (circular cylinder, square cylinder, NACA0012 airfoil) in a uniform flow are presented and the generation and propagation mechanisms of the sound are discussed. The unsteady compressible Navier-Stokes equations are solved by a highly-accurate finite difference scheme over the entire region from near to ...

We derive analytical expressions for the solid angle subtended by a right finite circular cylinder at a point source with cosine angular distribution in the case where the source direction is parallel to the cylinder axis. As a subsidiary result, an expression for the solid angle subtended by a disc detector at a spread disc source is also provided, in the case where the two discs have a common...