A novel coalescence kernel with high predictive properties is constructed to be used within the population balance framework. The includes product of a collision frequency term and binary probability expression. expression employs critical velocity estimations from film drainage simulations that also considers particle surface kinetic energies. Thus, proposed possesses characteristics all three commonly approaches: drainage, energy, models. having certain angle considered through density...

Coalescence in the presence of low surfactant concentrations is investigated via a film drainage model, where interface Boussinesq surface fluid with concentration dependent physical properties. Three cases are considered representing systems water continuous phase and dispersed either high viscosity droplets, droplets comparable to or gas bubbles. In former, immobilization due viscosities, whereas latter two, Marangoni flow plays an important role, too. When bubbles considered, it seen that...

The effect of the constant relative approach velocity two Newtonian fluid particles on their coalescence is investigated via a film drainage model. interfaces are deformable and allowed to have any degree mobility. thinning equation derived based lubrication theory, tangential interface determined Boundary Integral Method (BIM). details for treatment inherent singularity in BIM provided. As increases, regardless strength van der Waals forces value viscosity ratio (or interfacial mobility),...

The effect of the surface viscoelasticity on drainage film between two gently colliding fluid particles is studied. interfaces bounding thin are treated as deformable ones, which follow analogous Upper Convected Maxwell model. presence elastic forces interface found to delay viscous response interface, i.e., behaves inviscid for a certain duration before recovering Newtonian behavior. this scales with magnitude Weissenberg number, whereas determine time at deviation from behavior begins....

The collision of two fluid particles with similar sizes approaching each other time dependent velocities is studied in this work via a film drainage model that can render both coalescence and rebound. equations are simplified following the lubrication theory interfaces treated as deformable ones. particle governed by force balance includes added mass, drag, buoyancy forces. stems from pressure build up within due to interfacial deformations, its presence enables bounce, provided becomes...

Initially motivated by the analysis of flow dynamics synovial fluid, taken as non-Newtonian, this paper also reports on a numerical challenge which occurred unexpectedly while solving momentum equation model. The configuration consists two infinitely long horizontal parallel flat plates where top plate is sheared at constant speed and bottom fixed. fluid shows shear-thinning rheology, furthermore it thickens with hyaluronic acid (HA) concentration, i.e., chemically-thickening. Accordingly,...

This paper discusses the momentum jump condition across a viscous interface, which shows Newtonian behavior, i.e., is Boussinesq surface fluid, by reviewing and expanding works of Edwards et al. (1991) Slattery (2007). The necessary geometrical/mathematical tools for derivation condition, itself are systematically derived different cases defined based on functional form surfaces. interfaces with various degrees deformability presented both arbitrary coordinate systems explicitly in...

The drainage of the non-Newtonian film between two approaching fluid particles are studied. continuous phase is a generalized Newtonian that obeys power-law model, and deformable particle interfaces allowed to have any degree tangential mobility. interaction gentle collision with constant relative approach velocity. equations simplified by using lubrication theory in thin limit combined boundary integral method. effect behavior on coalescence time investigated through power index. It found...

This work studies the collision of fluid particles (bubbles or droplets) in non-Newtonian media whose viscosity obeys power-law model, by analyzing behavior drainage film between particles. The model considers a time-dependent velocity governed force balance over each particle, which renders estimation both coalescence and rebound possible as result critical separating two regimes. Results indicate that shear-thinning continuous medium favors coalescence, whereas shear-thickening films...

Process intensification by cavitation is gaining widespread attention due to the benefits that intense bubble collapse conditions can provide, yet, several knowledge gaps exist in modelling of such systems. This work studies numerical prediction single dynamics and various approaches be employed estimate changes chemical composition cavitating bubbles. Specific emphasis placed on radical production rates during computational performance, with aim coupling flow models for reactor...

In any real system with dispersed bubbles, dissolution and impurity/surfactant presence will affect the bubble dynamics to a certain extent. This work aims determine quantitative conditions under which these mechanisms significantly change coalescence behavior time in system. To achieve this, of two gently colliding, deformable, dissolving bubbles is investigated through film drainage study surfactant presence. The model analyzed thin limit coupled boundary integral method. found slow down...

The boundary integral formulations of the linear differential equations are widely used in modeling, as they reduce size problem by one dimension. Specifically, corresponding formulation Stokes has become an part coalescence/film drainage models providing tangential velocity at fluid particle interface without requiring any solution inside particle. This work presents full derivation coordinate invariant form a compact manner, well specific that can be employed axisymmetric and...