Defining Lagrangian Phases

A Lagrangian phase is used to define the solid particles in the simulation. The phase requires specific models and properties to characterize its behavior. In this case, the solid particles are cylindrical tablets, with the material properties set by the user. In a later step, you define interactions between tablets and the mixer walls and between other tablets.

To define the Lagrangian phase:
  1. Right-click the Lagrangian Multiphase > Lagrangian Phases node and select New > Free-stream Phase.
  2. Rename the phase as tablet.
  3. Right-click the tablet > Models node, click Select Models, and select the following models in order:
    Group Box Model
    Particle Type DEM Particles
    Optional Particle Forces Deactivate Pressure Gradient Force (selected automatically)
    Particle Shape Cylindrical Particles
    Material Solid
    Equation of State Constant Density
    Optional Models Passive Scalar
  4. Click Close.
  5. Expand the Lagrangian Multiphase > Lagrangian Phases > tablet > Models > Solid node.
  6. Select the Rubber node and rename it as tablet.
  7. Expand the tablet > Material Properties > Density node.
  8. Select the Constant node and set Value to 1100.0 kg/m^3.
  9. Right-click the Passive Scalar > Passive Scalars node, and select New.
  10. Rename the newly created Passive Scalar sub-node Spray Residence Time.
    NoteAlthough defined, the passive scalar remains inactive in this first phase of the tutorial.

A default boundary interaction is specified for all wall boundaries in the Lagrangian phase itself. For details, see the node Lagrangian Multiphase > Lagrangian Phases > tablet > Boundary Conditions > Wall.