Investigation and modeling of bubble-bubble interaction effect in homogeneous bubbly flows

摘要

The effect of bubble-bubble interaction in homogeneous bubbly flow is investigated by direct numerical simulation and a bubbly mixture model for bubbly shock flows at void fraction 0.4%-13%. It is found that the bubble-bubble interaction effect is significant at void fraction higher than O(1)% and decreases the amplitude and wavelength of the macroscale oscillations in the dispersive shock structure. For the modeling of bubble-bubble interaction effect, the locally volume averaged Rayleigh-Plesset (LVARP) equation, which is an extended version of the original Rayleigh-Plesset equation, is proposed in the present study. The results of bubbly mixture model using LVARP agree well with the direct simulation results for bubbly shock flows at void fraction up to 13%. The bubble-bubble interaction in nonuniform bubbly flows is also investigated in bubbly flows with randomized initial bubble positions. It is found that the LVARP model predicts the ensemble averaged behavior with reasonable accuracy.