Hydroacoustics of turbulent flow over superhydrophobic and oscillating cylinders

Hydroacoustic analysis of three-dimensional, turbulent flow over superhydrophobic and oscillating cylinders has been performed at Re = 3900. A third -type Robin boundary condition has been utilized to apply superhydrophobicity over the surfaces including two different slip coefficients of 0.425 and 0.1. Regarding the acoustical analysis, the Ffowcs Williams-Hawkings acoustic analogy has been used to investigate the generation and propagation of sound. For the case of a stationary cylinder, superhydrophobicity leads to an 8 percent increase in the Strouhal number. Furthermore, the overall sound pressure level is reduced by an amount of around 6 decibels. It is indicated that at a constant amplitude, the mean drag coefficient and the root -mean -square lift coefficient experience a 40% and 750% increase, respectively. Also, the maximum and the overall sound pressure levels escalate as the frequency ratio increases. The maximum amount of elevation in terms of the generated sound is 25 decibels for the synchronized case. Further analysis of the sound directivity proves that both the stationary cylinder and the lock -in cases of the transversely oscillating cylinder demonstrate symmetrical patterns in the dipole form. However, the non -synchronized states of the oscillation exhibit asymmetrical trends and deviate from the dipole pattern.