Experiments on sound radiation in flow past two side-by-side square cylinders

Abstract

Vortex shedding and sound radiation from two side-by-side square cylinders was examined experimentally at low-Mach-number flow. The center-to-center distance (L∕d) between two cylinders was 3.6, 4.5 and 6.0 which are still in the regime of non-biased flow. At L∕d = 3.6 and 4.5, the wake behind the cylinders showed symmetric vortex shedding which generate the in-phase sound pressure. The vortex shedding exhibited a high spanwise coherency and thus strong soundwas radiated compared to that in a single-cylinder case. It was also shown that when a short splitter plate with c∕d = 0.2 was glued on the rear side of each cylinder, the sound pressure level was reduced significantly.