An Investigation of the Propagation of Pressure Perturbations in Bubbly Air/Water Flows

Dispersion and attenuation was measured for standing waves in a vertical waveguide filled with a bubbly air/water mixture. The propagation speed of pressure pulses was also measured. The data were compared with a two-fluid model for a range of values of the virtual volume coefficient, C_VM. The experimentally determined C_VM was found to be a function of global void fraction (〈α〉). Moreover it was noted that this C_VM was less strongly related to void fraction than those proposed by Zuber (1964) and Van Wijngaarden (1976).