An experimental investigation has been carried out on interference effects in vortex-shedding from a heated circular cylinder in the crossflow Reynolds number (
Re*=2, 500) subjected to the acoustical vibrations whose
SPL is over 130 =dB. Due to acoustic interferences on vortex-shedding, the separation point is slightly shifted downstream around its surface, the laminar-turbulent transition in the separated shear layer is promoted, the shear layer becomes thicker, the vortex-shedding position gets nearer to it, the strength of the vortices is also increased, and its form drag coefficient increases. There is a critical value for the applied sound pressure level over which powerful effects on vortex-shedding is observed. The vortex-shedding frequency
fs is a little changed by the applying sound field. The change is remarkable for sound pressure level exceeds a critical value (=130dB) and the cylinder is heated. These phenomena are analogous to the thermoacoustic streaming in the natural convection.
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