Strouhal numbers for flow past a combined circular–rectangular prism

Unsteady loading frequencies due to cross-flow on a novel drop wire design are investigated with results presented in terms of the Reynolds number, the Strouhal number and the angle of attack. The wire model has a cross section which is composed of a circle and attached rectangle. Comparison is made to results in the literature for flow over circular and square cylinders. The study shows that wires of this design combining both rounded and square edged surfaces may be particularly susceptible to flow induced vibrations due to vortex shedding, due to the wider range of excitation frequencies (Strouhal numbers) they experience.