Reduction of fluid forces acting on a single circular cylinder and two circular cylinders by using tripping rods

Alam, Md. Mahbub; Sakamoto, Hiroshi; Moriya, M.

doi:10.1016/j.jfluidstructs.2003.07.011

Cited by 79 publications

(33 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The fluid forces on two side-by-side square cylinders cannot be the same as on two circular cylinders, as may be inferred from distinct surface pressure distributions around the two types of cylinders (e.g. Vickery 1966;Achenbach 1968;Batham 1973;Bearman & Obajasu 1982;West & Apelt 1993;Alam et al 2002Alam et al , 2003bAlam, Sakamoto & Zhou 2005). Then, how do steady and unsteady fluid forces and St vary with T /d, in particular in the turbulent subcritical flow regime?…”

Section: Introductionmentioning

confidence: 99%

“…Previous investigators (Hori 1959;Bearman & Wadcock 1973;Zdravkovich & Pridden 1977;Jendrzejczyk & Chen 1982;Zhou et al 2001) noted that C L on two side-by-side cylinders was always repulsive and decreased with increasing T /d. Alam, Sakamoto & Moriya (2003b) measured attractive C L at very small T /d, i.e. T /d = 1.1, where the gap flow swept around one cylinder for a longer peripheral length, forming a separation bubble (see also Alam & Zhou 2007a).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The wake of two side-by-side square cylinders

2011

View full text Add to dashboard Cite

Aerodynamic interference between two cylinders involves most of the generic flow features associated with multiple structures, thus providing an excellent model for gaining physical insight into the wake of multiple cylindrical structures. This work aims to provide an experimental systematic study of the flow behind two side-by-side square cylinders. The square cylinder is a representative model for bluff bodies with sharp corners, characterized by a fixed flow separation point, which are distinct from those of continuous curvature with oscillating separation points, typically represented by the circular cylinder. Experiments were performed at a Reynolds number Re of 4.7 × 10 4 and a cylinder centre-to-centre spacing ratio T /d (d is the cylinder height) of 1.02-6.00. The flow was measured using different techniques, including hot wires, load cell, particle imaging velocimetry and laser-induced fluorescence flow visualization. Four distinct flow regimes and their corresponding T /d ranges are identified for the first time on the basis of the flow structure and the Strouhal number. Physical aspects in each regime, such as interference between shear layers, gap flow deflection and changeover, multiple flow modes, entrainment, recirculation bubble, vortex interactions and formation lengths, are investigated in detail and are connected to the characteristics of the time-averaged and fluctuating fluid forces. The flow displays a marked difference in many facets from that behind two side-by-side circular cylinders, which is linked to their distinct flow separation natures. A crucial role played by the gap flow and its passage geometry in contributing to the observed difference is also unveiled.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The wake of two side-by-side square cylinders

2011

View full text Add to dashboard Cite

show abstract

“…James and Truong [48], Alam et al [49], or by placing a small cylinder in the shear layer, e.g. Sakamoto et al [50], Alam et al [51].…”

Section: Force/flow Control Mechanismsmentioning

confidence: 99%

Two interacting cylinders in cross flow

Alam

Meyer

2011

Phys. Rev. E

View full text Add to dashboard Cite

show abstract

“…Flow around two tandem circular rigid cylinders has been investigated from the subcritical Re to the super critical (e.g., Okajima, [1]). In general this flow may be classified as three regimes based on L/D (Zdravkovich [2]): (1)extended-body regime, where L/D is from 0 to 0.5 and the free shear layers separated from the upstream cylinder over shoot the downstream; (2) reattachment regime, where L/D is between 0.5 and 3,and the shear layers reattach on the downstream cylinder; and (3)co-shedding regime, where L/D > 3 and the shear layers roll up alternately, forming a vortex street in the gap between as well as behind the cylinders. Arie et al [3] pointed out that fluctuation in drag force acting on both cylinders is weakly dependent on spacing.…”

Section: Introductionmentioning

confidence: 99%

Experimental study of flow around two grooved cylinders arranged in tandem

Ladjedel

Adjlout

Hachim

et al. 2014

EPJ Web of Conferences

View full text Add to dashboard Cite

Abstract. In the present paper, the influence of longitudinal grooves placed on tubes is investigated for different configurations in tandem for three Reynolds number. Each cylinder has two grooves on the external surface at 90° and 270° degrees. The experiments are carried out using a subsonic wind tunnel. The pressure distributions along the tubes are determined for a variation of the azimuthal angle from 0 to 360 degrees. The drag and lift forces are measured using the TE 44 balance. The results show that the upstream cylinder pressure is greater than for second one. There is a difference in the pressure coefficient as well as the pressure drag for configuration smooth-smooth and grooved-grooved.

show abstract

Reduction of fluid forces acting on a single circular cylinder and two circular cylinders by using tripping rods

Cited by 79 publications

References 44 publications

The wake of two side-by-side square cylinders

The wake of two side-by-side square cylinders

Two interacting cylinders in cross flow

Experimental study of flow around two grooved cylinders arranged in tandem

Contact Info

Product

Resources

About