Abstract
The effects of optional structures with shape change along longitudinal axis on wind load of rectangular cylinders with side ratio 3 were studied experimentally in a wind tunnel. The present Strouhal number and drag coefficient of rectangular cylinder without optional structures agreed well with existing results. Drag coefficient increased while coefficient of fluctuating lift decreased significantly with optional structures. Peak frequency became one third, which indicated transition from reattachment-type of flow to perfect separation type. It was observed that 2 peak values in spectrum of lift force for optional structures with shape change longitudinal axis were smaller than other cases.
