Angular distribution of pressure on a cylinder oscillating sinusoidally in water

In this study, an investigation of the variation of the unsteady pressure distribution around a circular cylinder was conducted. The model was oscillated sinusoidally in a water tank by means of a scotch yoke. The instantaneous pressures were measured by means of miniature strain gage pressure transducers. Ranges of oscillatory speeds were from 9.8 to 58.6 cycles per minute with amplitudes of oscillation of 1, 2, U- and 6 inches. A series of time-dependent unsteady distributions of circumferential pressure are presented in the form of diagrams of pressure coefficients versus angular position about the cylinder wall from 0 to 180 degrees. The pressure drag was determined by integration of the pressure coefficient. The magnitude of the forces were found to depend on the amplitudes of oscillations and frequencies of the displacements of the amplitudes and frequencies of oscillations of the cylinder. These results are consistent with what could be anticipated in advance.