Towards best practice recommendations for turbulence modelling of high-pressure homogenizer outlet chambers – Numerical validation using DNS data

Emulsifier adsorption kinetics influences drop deformation and breakup in turbulent emulsification

“…Simulations are based on the CaNS implementation, 59 which has been extensively tested and validated in previous studies. For emulsification under conditions like those investigated in the present study, good agreement has previously been found between simulations and high-speed breakup visualizations 60 as well as between simulations and emulsification experiments. 61 Traditionally, when neglecting emulsifier adsorption dynamics and interfacial rheology, three factors are expected to control breakup: the Weber number (We), the disperse to continuous phase viscosity ratio (m D /m C ), and the disperse to continuous phase density ratio (r D /r C ).…”

“…Turbulent flows are highly stochastic, and each drop subjected to it will take a different trajectory and interact with different turbulent structures. 10,36,40,46,60 Looking at a larger collection of viscous drops (m D /m C = 20) subjected to conditions of We = 5, we see mainly two types of deformation processes: 41 some drops-upon being injected in the turbulence-encounter sufficiently forceful turbulent stress to immediately go into a monotonous deformation that eventually leads to breakup (cf. Fig.…”

Insights into the hydrodynamics in the annular pipe of industrial‐scale top‐blown smelting furnace

“…However, the computations of these two models typically lack the resources for attaining sufficient grid resolution to adequately evaluate industrially relevant devices due to the expensive computational cost. [17,18] The Reynolds-averaged Navier-Stokes (RANS) approach, which is derived by substituting the average and random components of the velocity and pressure to the N-S equations, is performed to predict the turbulence flow of the fluid. Moreover, the Reynolds stress model (RSM) and shear stress transport (SST) k-ω model are commonly utilized to predict swirl flow.…”

High Pressure Homogenization – An Update on its Usage and Understanding

“…License: CC BY-NC-ND 4.0 observed that while RANS-CFD can reasonably model flow in the inlet and valve gap, it is inaccurate in the outlet region both in terms of the velocity profile and the production of turbulent kinetic energy. More recent studies have employed more sophisticated though computationally costly methods such as Large Eddy Simulation (LES) on the whole homogenizer valve (Taghinia et al, 2016(Taghinia et al, , 2015 and Direct Numerical Simulation (DNS) on the outlet region (Olad et al, 2022a(Olad et al, , 2022b) and were able to provide much more accurate descriptions of the flow, even in the outlet region. The interested reader is referred to Olad et al, (2022a) for a state-of-the-art discussion on best practices in applying turbulence models in HPH CFD studies.…”

“…and provide significant insight to the flow characteristics. These methods can also be used to generate more accurate estimates of 𝜖𝜖̅ (Olad et al, 2022a) which are then used to compute a property of interest using the methods outlined, or alternatively the local flow data can be used directly (e.g., see Casoli et al, (2010)).…”