THE EFFECT OF INCLINATION ON THE STROUHAL NUMBER AND OTHER WAKE PROPERTIES OF CIRCULAR CYLINDERS AT SUBCRITICAL REYNOLDS NUMBERS.

Abstract : A brief experimental investigation was made to determine the effect of inclination on the Strouhal Number of circular cylinders at Reynold's numbers from 4,000 to 65,000. It was found that the Strouhal Number based on the normal velocity component remained constant to a good approximation. Spectral techniques showed that the energy of the shed vortices dispersed in frequency and decreased in significance with increasing inclination, such that for angles less than 40 degrees the shedding energy was negligible compared to the general wake turbulence energy, at 7.5 diameters downstream from the cylinder. Other wake properties were briefly investigated. These included the decay of the u-component of turbulence downstream and the behaviour of the wake spectra with inclination, speed and wake location. (Author)