Eulerian Multiphase (EMP)
The Eulerian Multiphase (EMP) model is suitable for fluids that can be considered continuous and interpenetrating, rather than discrete in nature. Typically a one phase would be considered to exist as unresolved modeled droplets or bubbles within another. The phases can interact both in terms of the drag and lift forces acting between them, but also in terms of heat and mass transfer, such as inter and intra phase reactions, and wall and bulk boiling.
Dispersed particle flows can also be modeled as an Eulerian phase, allowing applications such as granular flows in fluidized bed reactors to be simulated. The Solid Pressure Force model is available for granular flows approaching the packing limit, and particle size distributions can be handled using the S-Gamma model.
Eulerian Multiphase Mixture
The Eulerian Multiphase Mixture model is a lightweight model that solves a single set of transport equations for the momentum, mass and energy transport of a mixture, which is made of a liquid and it's vapor, typically water and steam.
Volume Of Fluid (VOF) Model
Within this Eulerian framework, STAR-CCM+ also has the Volume Of Fluid (VOF) model which is used for the simulation of immiscible free surfaces, such as the development of waves around a ship hull (and consequential drag), or slugging flow in a pipe. To assist in the setting up of VOF cases, the model allows you to define VOF waves which are then used to initialize the VOF calculation and to provide suitable profiles at boundaries, vastly simplifying the setup of such cases. These waves can be superimposed to allow for the modeling of any scenario.
Fluid Film Model
Also within the Eulerian framework, the Fluid Film model allows thin fluid films to be modeled on the surface of your geometry. Typical applications include vehicle soiling, aircraft (anti) icing, oil films on the internal surfaces of automotive engines and gas turbines, spray-cooling systems, and ink-jet printers. The fluid film can interact with other phases, accepting impinging droplets from Lagrangian or Dispersed phases and allowing droplets to be shed by film stripping. The film can condense from and evaporate to Eulerian phases and boiling of the film can also be modeled.
Dispersed Multiphase (DMP)
The Dispersed Multiphase model (DMP) makes the simulation of applications such as aircraft deicing and anti-icing, and vehicle soiling and water management take a fraction of the time. These applications previously required the Lagrangian Multiphase (LMP) model. The Dispersed Multiphase model is a lightweight, computationally efficient model, which is typically used to model tiny water or rain droplets in wet free-stream air before they impinge on a vehicle or other object. The DMP model treats droplets as a continuous background phase superimposed on the single phase primary flow. This results in a model which is very much less computationally expensive than the Lagrangian equivalent, without the need for the full physics capability of Eulerian Multiphase (EMP).
Smart Hybrid Approaches and Multiphase Interaction Models
Whilst each of these multiphase models is most suited to a different flow regime, many real flow problems involve multiple flow regimes. To address this, STAR-CCM+ provides a number of hybrid approaches and multiphase interaction models. One such approach is the EMP Large Scale Interface model which combines the benefits of VOF and Eulerian Multiphase, allowing a single multiphase model to capture both free surfaces and dispersed flows of bubbles and droplets (http://www.cd-adapco.com/blog/david-mann/star-ccm-v1002-preview-get-best-both-worlds-large-scale-interface-model). Another such approach is the VOF-Fluid Film multiphase interaction model, which allows films or variable thickness to be represented by Fluid Film where the film is thin and VOF where the film is thick or pooling (http://www.cd-adapco.com/blog/david-mann/star-ccm-v1002-preview-smart-hybrid-multiphase-modeling-vof-fluid-film-and). These smart hybrid approaches open up many new applications at the minimum computational cost.
In addition to the comprehensive physics of the Eulerian Multiphase Model, the ease-of-use for streamlined setup of complex multiphase problems makes STAR-CCM+ the preferred solution for Multiphase applications.