DEVELOPMENT OF A K-EPSILON MODEL FOR BUBBLY 2-PHASE FLOW

An extension of the k-epsilon model for bubbly two-phase flow is propo sed and tested against experimental data. The basic assumption made is that the shear-induced turbulence and bubble-induced turbulence may b e linearly superposed. This assumption results in a model with two tim e constants that matches both homogeneous two-phase turbulence data (L ance and Bataille, 1991) and pipe data (Serizawa, 1986). The coefficie nts of the single-phase k-epsilon model have not been modified and onl y one additional coefficient is required: the virtual volume coefficie nt of the bubbles, which may be determined from first principles. This model not only agrees with the data trends, but it also predicts the turbulence suppression which has been measured for high Reynolds numbe r bubbly air/water flows in pipes.