Vortex shedding from spheres at Reynolds numbers from 3Y.10 to 4Y.10 in a uniform flow was investigated experimentally. Standard hot-wire technique were used to measure the vortex shedding frequency from spheres in a low-speed wind tunnel. Flow-visualization experiments were carried out in a water channel. Important results from the investigation were that (i) the variation of the Strouhal numb...

The paper presents the results of an experimental investigation of fluvial groynes conducted on a mobile bed scale model. The model reproduces a reach of the River Po, Italy, in which a series of groynes have been designed to improve navigability during dry periods. The experiments were conducted using light plastic material. The density and the grain size of the material were calibrated accord...

An experimental study was conduct to suppress the vortex shedding from a circular cylinder by using a suction flow control method. The suction flow control was accomplished using two suction holes located on the test cylinder model at an angle of 90.0 degrees in relation to the oncoming flow direction. In addition to measuring the pressure distributions around the test model, a high-resolution ...

Optimal control theory is combined with the numerical simulation of an incompressible viscous flow to control vortex shedding in order to maximize lift. A two-dimensional flat plate model is considered at a high angle of attack and a Reynolds number of 300. Actuation is provided by unsteady mass injection near the trailing edge and is modeled by a compact body force. The adjoint of the lineariz...

A numerical study is carried out to investigate the laminar forced convection heat transfer from a circular cylinder. The fluid is assumed to be incompressible, the Reynolds number ranged from 0.1 to 1000, and the Prandtl number was equal to 0.7. The range of study includes heat transfer in creeping flow (Re40). The equations were discretized by a control-volume-based finite difference techniqu...

We develop a reduced order model for large-scale unsteadiness (vortex shedding) in a two-dimensional diffuser and study the mechanisms of active flow separation control. This model can estimate the vortex shedding frequency for inviscid flows by accounting for the accumulated vorticity flux in the diffuser. The model can also predict the stagnation pressure loss, which consists of two parts: A ...

[1] Measurements of intrawave sediment entrainment processes are reported above ripples under irregular waves generated in a large‐scale flume facility. The data consist of substantive observations of small‐scale processes collected at high spatial and temporal resolution under irregular wave forcing, typical of coastal environments. Acoustic measurements were made of water velocities, bed form...

A general method based on adjoint formulation is discussed for the optimal control of distributed parameter systems (including boundary parameter) which is especially suitable for large dimensional control problems. Strategies for efficient and robust implementation of the method are described. The method is applied to the problem of controlling vortex shedding behind a cylinder (through suctio...

The present study investigates numerically the phenomenon of vortex-shedding and its suppression in twodimensional mixed convective flow past a square cylinder under the joint influence of buoyancy and free-stream orientation with respect to gravity. The numerical experiments have been conducted at a fixed Reynolds number (Re) of 100 and Prandtl number (Pr) of 0.71, while Richardson number (Ri)...

In order to study the turbulent structure of wake flow around the rear view side mirror of a passenger car, moment property and energy spectra in the mirror wake and fluctuating pressure distribution on the mirror surface have been measured by several experimental tools in an open circuit wind tunnel at the Reynolds number of 2 × 105. It was found that time-averaged streamwise velocity very nea...