Defining the Coarse Grain Particles

You use a Lagrangian phase to define the solid particles in the simulation. You use the Parcel Contact Coarse Grain particle shape model, which is well suited for fluidized bed applications, where accuracy of particle-fluid interactions is important. In this model, each simulated particle is a parcel that statistically represents multiple smaller identical particles. The model calculates fluid-particle interactions on a single representative particle and applies the result to all of the smaller particles in the parcel. The number of individual particles per coarse-grained parcel depends on the parcel and particle sizes that you specify for the injector later on.

To define the coarse grain particles:
  1. Right-click the Continua > Physics 1 > Models > Lagrangian Multiphase > Lagrangian Phases node and select New > Free-stream Phase.
  2. Rename the new phase to Particle.
  3. Double-click the Particle > Models node and select the following models, in order:
    Group Box Model
    Particle Type DEM Particles
    Pressure Gradient Force (selected automatically)
    Particle Shape Parcel Contact Coarse Grain
    Material Solid
    Equation of State Constant Density
    Optional Particle Forces Drag Force
    Optional Models Two-Way Coupling
  4. Select the Particle > Models > Drag Force > Drag Coefficient node and set Method to Gidaspow.
  5. Set up the material properties of the particles.
    1. Expand the Models > Solid node and rename Rubber to Catalyst.
    2. Expand the Catalyst > Material Properties node and set the following properties:
      Property Value
      Density 2200.0 kg/m^3
      Young's Modulus 100.0 MPa
  6. Save the simulation.