Strouhal number

Turbulence

Aerodynamic drag

Engineering

Aerospace engineering

Materials science

Reynolds number

Square (algebra)

Aerodynamics

Drag

Vortex shedding

Physics

Lift-induced drag

Mathematics

Zero-lift drag coefficient

Cylinder

Drag coefficient

Geometry

Mechanics

The Journal of the Japan Society of Aeronautical Engineering

An experimental study is carried out on the aerodynamic drag of rectangular cylinders, where the REYNOLDS number ranges up to 6×104. It is revealed that the drag coefficient, CD, varies con-siderably with the d/h ratio of rectangles, and that the maximum value of CD is as high as 2.6 for d/h of 2/3 compared with CD of about 2.0 for the cases of flat plate and square cylinder (Fig.1). The STROUHAL number of the shedding vortices, on the contrary, remains approximately constant for d/h up to 1.0, decreases slowly for larger values of d/h, and then increases abruptly at d/h ratio of about 2.8 (Fig.2), where the flow reattaches on the lateral surfaces of the cylinder.

An Experimental Study on Aerodynamic Drag of Rectangular Cylinders