Multiphase Flow

Numerous CFD applications involve not just a single fluid phase but, rather, multiple phases. ANSYS Fluent is a leader in multiphase modeling technology. Its varied capabilities allow engineers to gain insight into equipment that is often difficult to probe. A complete suite of models allows ANSYS Fluent to capture the interplay between multiple fluid phases like gases and liquids, dispersed particles and droplets, and free surfaces.

For immiscible multiphase flows, ANSYS Fluent offers the volume-of-fluid (VOF) model. For multiphase applications such as spray dryers, liquid fuel sprays, continuous fiber drawing and coal furnaces, the discrete phase model (DPM) can be used. The simple DPM model allows for dilute droplet or particulate flows. For flows with denser droplets or particulates concentration, ANSYS Fluent offers the dense DPM (DDPM) model. Furthermore, accurate tracking of the collisions between large solids particles can be taken into account thanks to the ANSYS Fluent discrete element particles (DEM) model. It is also possible to simulate complex phenomena like erosion.

For interpenetrating fluids or phases, ANSYS Fluent software makes use of the Eulerian multiphase model with its separate sets of fluid equations, as well as a more economical mixture model. Both models can also handle granular flows. 

The Eulerian multiphase model features a wealth of options to capture the exchange of mass, momentum and energy. This includes numerous drag and nondrag force models as well as robust models for phase change due to cavitation, evaporation, condensation and boiling. Additionally, population models allow the simulation of the effect of turbulent breakup and coalescence of different bubble sizes.

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 Bubbles in a fluidized bed