Modeling drop breakage using the full energy spectrum and a specific realization of turbulence anisotropy

Abstract

The assumption of homogeneous isotropic turbulence when modeling drop breakage in industrially relevant geometries is questionable. We describe the development of an anisotropic breakage model, where the anisotropy is introduced via the inclusion of a perturbed turbulence spectrum. The selection of the perturbed spectrum is itself motivated by our previous large‐eddy simulations of high‐pressure homogenizers. The model redistributes energy from small to large scales, and assumes that the anisotropic part of the Reynolds stresses is confined to the energy‐containing range. The second‐order structure function arising from the perturbed spectrum is used in the standard framework of Coulaloglou and Tavlarides to calculate breakage frequency. While the base model exhibits non‐monotonic behavior (by predicting a maximum value for a certain drop size), the effect of anisotropy is shown to increase breakage frequency in length scales larger than this peak, thereby reducing non‐monotonicity. This effect is more pronounced for small turbulence Reynolds numbers.

Drop breakage in a single‐pass through vortex‐based cavitation device: Experiments and modeling

“…, and are model parameters. Equation () contains two terms: the first term containing represents the frequency of the droplet breakage, and the second term containing represents the probability of breakage given in terms of the complementary error function (erfc) 43 . The parameter C 3 influences breakage frequency and thereby influences the broadness of DSD (without significantly affecting the location of the peak in DSD).…”

Experimental study on the differences between bubble and drop breakages in agitated turbulent flows

“…According to previous studies, the breakage mechanism could be classified into four types 4,5 : turbulent eddy impact, viscous shear stress, shearing shedding, and interface instability. Turbulent eddy impact mechanism was widely studied by many researchers 6–21 . Many models of breakage frequency and DSD were proposed by considering different breakage criteria, 6–12 multiple breakage, 13,14 full energy spectrum, 15–18 and internal flow redistribution 19,20 …”

“…Turbulent eddy impact mechanism was widely studied by many researchers 6–21 . Many models of breakage frequency and DSD were proposed by considering different breakage criteria, 6–12 multiple breakage, 13,14 full energy spectrum, 15–18 and internal flow redistribution 19,20 …”

“…Turbulent eddy impact mechanism was widely studied by many researchers. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] Many models of breakage frequency and DSD were proposed by considering different breakage criteria, [6][7][8][9][10][11][12] multiple breakage, 13,14 full energy spectrum, [15][16][17][18] and internal flow redistribution. 19,20 To verify these models, a large number of experimental data on fluid particle breakage are required.…”