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The effect of freestream turbulence on the flow past a circular cylinder (tube) was studied experimentally for Reynolds numbers between 2 x 104 and 6 x 104. Investigations were carried out for uniform (non-turbulent) flow and for turbulent flows having turbulence intensities between 1.3 and 4.1%. The variations in the pressure forces and shedding frequencies were found to be related to the variati

This paper concerns an experimental investigation of the flow around and pressure forces on fixed (non-vibrating) rectangular cylinders at angles of attack 0° - 90°. Pressure forces and moments for cylinders with side ratios B / A = 1, 1.62, 2.5 and 3 (shortest side A = 20 ram) were estimated from measurements of static pressure distributions at mid-span. Wake frequencies and associated Strouhal n

The investigation is concentrated on two important quantities – the Strouhal number and the mean base suction coefficient, both measured at the mid-span position. Reynolds numbers from about 50 to 4 × 104 were investigated. Different aspect ratios, at low blockage ratios, were achieved by varying the distance between circular end plates (end plate diameter ratios between 10 and 30). It was not pos

The flow around a smooth and rigid tube (circular cylinder) in cross flow has been investigated experimentally. The experiments were carried out in a closed-circuit low-speed wind tunnel. Two test tubes (diameters 41 and 120 mm, respectively) fitted with end plates were used. The fluctuating pressures on the tube surface were sensed by microphones in pinhole arrangements while the modulus of the s

An experimental investigation of surface pressure distributions (mean and r.m.s.) on two tubes (circular cylinders) mounted in an in-line or tandem arrangement was carried out in a low-speed, closed-circuit wind tunnel. The measurements were mainly performed at a subcritical Reynolds number, Re = 2·0 × 104, at three different turbulence intensities of the approaching cross-flow (0·1, 1·4 and 3·2%)

Calculations of unsteady two-dimensional-flow around rectangular cylinders at incidence are presented. The Reynolds numbers are low ( ⩽ 200), so that the flow presumably is laminar. The results are in reasonable agreement with the indeed scarce experimental data available at these low Reynolds numbers. An incompressible SIMPLEC code is used employing non-staggered grid arrangement. A third-order Q

Calculations of unsteady 2D flow around a square cylinder at incidence (α=0°−45°) are presented. The Reynolds numbers are low (Re=45–200) so that the flow is presumably laminar. A von Kármán vortex sheet is predicted behind the cylinders with a periodicity which agrees well with experiments. An incompressible SIMPLEC code is used with a non-staggered grid arrangement. A third-order QUICK scheme is