Drag reduction of an object is the major concern in many engineering applications. Experimental studies have been carried out on circular cylinder with helical grooves in a subsonic wind tunnel. Different cases of helical grooves with different pitches, helical groove angles and number of starts of helical groove on circular cylinder are tested. Experimental results show the drag coefficient is...

Turbulence studies were made in the wake of a rotating circular cylinder in a uniform free stream. The interest was to examine the turbulence properties at the suppression of periodicity in vortex formation process. An experimental study of the turbulent near wake of a rotating circular cylinder was made at a Reynolds number of 9000 for velocity ratios, λ between 0 and 2.7. Hot-wire anemometry ...

In this paper, effects of EHD actuators on hydrodynamic behavior and heat transfer of air flow over a circular cylinder were considered. Pressure and temperature distributions around the cylinder were measured in presence of wire-plate EHD actuators. The Reynolds number based on cylinder diameter (d) were 3500, 7000. Experiments were performed for various configurations. Based on obtained resul...

Functionally graded materials (FGMs) enable one to tailor the spatial variation of material properties so as to fully use the material everywhere. For example, in a hollow circular cylinder one can vary, in the radial direction, the material moduli to make the hoop stress constant. Whereas the problem for a hollow cylinder with the inner and the outer surfaces circular has been studied, that of...

A known bifurcation scenario describing the development and interaction of Mode A and Mode B vortex shedding modes of a circular cylinder wake is extended to predict the Strouhal–Reynolds number profile over the three-dimensional transitions. The mode amplitudes are described by coupled Landau equations and, with frequency information being included by the addition of complex coefficients, the ...

Vortex shedding from a circular cylinder and from an inclined flat plate is computed with a finite volume CFD code with RNG k-ε turbulence model. The wake behind the circular cylinder consists of two trains of vortices of equal strengths. Dependence of vortex patterns on Reynolds numbers at Re between 10 and 10 is investigated. Flow over the inclined flat plate is asymmetric and unequal charact...

in this study, the characteristics of the wake around a rotating circular cylinder have been investigated experimentally. to this end, a cylinder with a circular cross-section of plexiglas with the length of 400 mm and a diameter of 20 mm have been tested in the wind tunnel. using existing methods, the characteristics of the wake and the drag coefficients of the model in different cases have be...

Safety analysis has been done for thick-walled circular cylinder under internal and external pressure using transition theory which is based on the concept of generalized principal Lebesgue strain measure. Results have been analyzed theoretically and discussed numerically. From the analysis, it can be concluded that circular cylinder made of functionally graded material is on the safer side of ...

Keywords: Flow around a circular cylinder Vortex-induced vibration Flow control Steady suction Mitigation of vortex-induced vibration a b s t r a c t In the present study, a flow control method is employed to mitigate vortex-induced vibration (VIV) of a circular cylinder by using a suction flow method. The VIV of a circular cylinder was first reproduced in a wind tunnel by using a spring–mass s...

A narrow strip has been introduced as a control element to suppress vortex shedding from a cylinder. The strip is set parallel to the cylinder axis, and the key parameter of control in this study is the strip position, which is determined by the angle of attack of the strip and the distance between the strip and the cylinder axis. A circular cylinder and a square cylinder were tested respective...