Numerical simulation of the turbulent flow around a triangular cylinder at Reynolds number of 45,000 is presented in this paper. A body force potential model is used to model the turbulent motion. This approach is able to model non-equilibrium turbulence accurately at a cost and complexity comparable to k-ε models. The numerical method used in this calculation is an unstructured staggered mesh ...

The Karman vortex street is a common flow phenomenon. In hydraulic machinery, it usually located downstream of the guide vanes and runner blades, which reduces performance may also cause fatigue damage to structure. latest research suggested that difference in velocity gradient on each side blade trailing edge have significant impact strength wake vortex. current work aims verify above conclusi...

In this paper a measurement of static pressure in the wake behind circular cylinder for different Reynolds numbers is presented. For purpose, probe with built-in transducer was used. The main goal to describe unsteady field and determine frequency generated Von Kármán vortex street. conducted low speed wind tunnel 110 mm diameter. results were compared an RANS simulation.

Detached Eddy Simulation on a 13 M grid is conducted for a KVLCC2 tanker hull form at drift angle 301. The objective is to identify and analyze the vortical structures, instabilities, and turbulent structures with analogy to the vortex breakdown and helical instability analysis for delta wing at large angles of attack. One shear layer, one Karman-like vortex shedding, and three helical mode ins...

Two-dimensional velocity fields around a freely swimming freshwater black shark fish in longitudinal (XZ) plane and transverse (YZ) plane are measured using digital particle image velocimetry (DPIV). By transferring momentum to the fluid, fishes generate thrust. Thrust is generated not only by its caudal fin, but also using pectoral and anal fins, the contribution of which depends on the fish's...

Our understanding of how variable wind in natural environments affects flying insects is limited because most studies of insect flight are conducted in either smooth flow or still air conditions. Here, we investigate the effects of structured, unsteady flow (the von Karman vortex street behind a cylinder) on the flight performance of bumblebees (Bombus impatiens). Bumblebees are 'all-weather' f...

his investigation was carried out to reveal the impact of solar radiation on wind flow structure and pollutant dispersion in an urban street canyon of aspect ratio of one using the computational fluid dynamic (cfd) technique. the simulation results (velocity and concentration data) show that heating from building wall surfaces and ground lead to strong buoyancy forces as the air is heated by th...

We study the behavior of an elastic loop embedded in a flowing soap film. This deformable loop is wetted into the film and is held fixed at a single point against the oncoming flow. We interpret this system as a two-dimensional flexible body interacting in a two-dimensional flow. This coupled fluid-structure system shows bistability, with both stationary and oscillatory states. In its stationar...

A direct numerical simulation (DNS) code is constructed for solving flow across a three-dimensional deformable bluff body. In the present study, DNS of flow across rigid and compliant cylinders is performed to evaluate the code and the drag reduction effect with a compliant coating. The Strouhal number of shedding of the Karman vortex is calculated and it agrees well with that reported in the l...