EDEM Creator - Set up the Model

Learn how to set up a simulation model and equipment, and define the generation of bulk materials using EDEM Creator.

To set up the model:
  1. Select the units of measurement to be used throughout EDEM.
    For more information about how to select units, see Select Units.
    1. Click Tools > Options... and then select the Units tab.
    2. In the Units tab, change the following measurement units:
      • Angle to degrees (deg)
      • Angular velocity to rpm
      • Length to mm
      • Charge to nano-Coulombs (nC)
      • Work Function to J
    3. Click OK.
  2. Specify a title and description for the model.
    1. Click Project in the Creator Tree.
    2. In the Detailed View, specify a title (Printer Simulation).
    3. Enter a description in the Description field.
    The model title and description is displayed in the Data Browser window. You can close the Data Browser window to allocate more space for the windows that will be used throughout this tutorial. If required, you can open the Data Browser window again by right-clicking the menu bar and selecting Data Browser.

Define the Bulk Material

The first step in setting up the model is to add bulk material and bulk material particle shapes to a model and define their interactions.

To define the bulk material:
  1. Add the bulk material.
    1. Right-click Bulk Material in the Creator Tree, select Add Bulk Material , and enter the name toner in the BulkMaterial1 highlighted field. Alternatively, you can also use the icons in the Toolbar.
  2. Define the bulk material properties and interactions.
    1. Select toner in the Bulk Material section.
    2. In the toner Properties dialog box, specify the Poisson's Ratio, Solids Density, and Shear Modulus.
  3. Define the bulk material interactions.
    1. In the Interactions section, click the icon.
    2. In the Select Material dialog box, select toner from the dropdown list to define the interaction between all elements made of the material 'Particle Material'.
    3. Specify the Coefficients as follows:


  4. Create a new particle shape after defining the bulk material and interaction properties.
    Note: Particles are made up of one or more spheres. In this case the particle is represented by a single sphere.
    1. Right-click toner in the Bulk Material section and then select Add Shape from Library > Add Single Sphere.
    2. Enter the name toner_particle in the Particle highlighted field.

      Optionally, you can rename the particle by right-clicking the particle and selecting Rename Particle.

  5. Define the spheres and properties.
    Note: Particles are made up of one or more spheres. In this lesson, the grain particle is assumed to be made from two spheres.
    1. In the Creator Tree, select toner_particle and then select Modify Shape in the Detailed View section.
    2. Set the Physical Radius of ‘sphere 1’ to 2.5 mm.
    3. In the toner_particle > Properties section, click Calculate Properties to define the mass, volume and inertia.

Define the Equipment Material

The next step in setting up the model is to add the equipment material which will be used in the simulation.

To define the equipment material:
  1. Add new equipment material.
    1. Right-click Equipment Material in the Creator Tree, and then select Add Equipment Material two times and enter the names 'magroller' and 'toproller' in the highlighted fields respectively.
  2. Define the equipment material properties.
    1. Select steel in the Equipment Material section.
    2. For both materials, specify the Poisson's Ratio, Solids Density, and Shear Modulus as follows:
  3. Define the bulk material - equipment material interaction.
    1. In the Interaction dialog box, click the icon.
    2. In the Select Material dialog box, select magroller and toproller from the dropdown list to define the interaction between elements made of 'toner' and elements made of 'magroller' and 'toproller'.
    3. Specify the coefficients as follows:

Define the Physics

The next step is to select the contact models that describe how elements behave when they come into contact with one another.

To define the Physics:

In this example, the printer model uses the Electrostatic Force model that involves the calculation of a force based on the proximity and charge of other elements in the simulation. In order to optimize the efficiency of the simulation, you can define a screening distance that determines the maximum distance a target object will experience force from another object.

  1. Select Physics in the Creator tree.
  2. Select Particle Body Force from the Interaction dropdown list.
  3. Click Edit Contact Chain and select Electrostatics.


  4. Click the icon to configure the force properties.
  5. In the Particle Body Force Parameter Values dialog box, set the following:


  6. Enable Tribocharging.
    Note: Tribocharging handles the transfer of charge due to the triboelectric effect, which is a type of contact electrification during which a certain material becomes electrically charged after being in contact with another material through friction.
    1. Select Particle to Geometry from the Interaction dropdown list.
    2. Click Edit Contact Chain and select the Tribocharging model.
    3. Click the icon to change the model.
    4. Set the Alpha value to 0.1.
    This will ensure that the particles gain charge and the Geometry loses charge.
  7. Click OK.

Define the Geometries

The next step in setting up the model is to define the screw auger Geometry used in the model.

To define Geometries:
  1. Import the magnetic roller Geometry that has already been created and is ready to be imported into EDEM.
    Note: The magnetic roller has been meshed to a resolution suitable for this electrostatic simulation. For reference, the mesh size of a Geometry that is required for electrostatic adhesion should be equal to or less than 1 particle diameter (in this case, 5mm).
    1. Right-click Geometries in the Creator Tree and then select Import Geometry.
    2. Navigate to the files magroll.msh and toproll.msh .
    3. In the Geometry Import Parameters dialog box, set the Units of measurement to Millimeters.
    4. Rename the Base Geometry section to Magroller and Top Geometry section to Toproller.
    5. Set the Material to magroller and toproller for each section.


  2. Specify the charge value for the rollers.
    Note: The toner particles need to be attracted to the magnetic roller as well as the top roller. To ensure this happens, the magroller Geometry must be assigned a small positive charge.
    1. Expand Magroller in the Geometries section of the Creator Tree and then select Electrostatics.


    2. Ensure that the Exclude from Electrostatics Calculations checkbox is not selected.
    3. Set the Starting Surface Charge as 40000 nC. This equates to approximately 15.8 nC per polygon.
    4. Repeat steps a-c for the Top roller, and set the Starting Surface Charge to 1e6 nC.
  3. Specify the roller kinematics.
    1. Select Magroller in the Creator Tree Geometries section.
    2. Right-click and then select Add Motion > Add Linear Rotation Kinematic.
    3. Select the newly created kinematic NewMotion 1, and then set the Initial Velocity to 50 rpm and the Axis of Rotation as follows:
    4. Repeat steps 1-3 for Toproller, and set the Initial Velocity to 25 rpm as follows:
  4. Create the particle factory volume.
    Note: Particle factories are used to define where, when and how particles will appear in a simulation. All factories must be based on a section of Geometry (whether 'real' or 'virtual'). This defines the area or volume in the model that produces the particles.
    1. Right-click Geometries in the Creator Tree.
    2. Select Add Geometry > Box and then enter the name factory into the highlighted field.
    3. Select the box and in the General section of the Detailed View set the type to Virtual, since the plate is not a physical part of the machinery.
    4. Expand factory in the Creator Tree and select the Transform subsection and set the position as follows:
    5. Select the Box subsection and specify the Number of Edges and Dimensions of the polygon as follows:
  5. Create the particle factory.
    Note: In this model, an unlimited stream of toner particles are produced using a dynamic factory. Since the Electrostatics Physics models have been set up, the charge option is now available in the factory.
    1. Right-click factory in the Creator Tree.
    2. Click Add Factory.
    3. Select the newly created factory and ensure that the Factory Type is set to dynamic.

      Optionally, right-click the new factory in the Creator Tree and then select Change Factory Type.

    4. In the Particle Generation dialog box, select Total Number and set the value to Unlimited.
    5. In the Generation Rate section, select Target Number and set the rate to 4000 particles/s.
  6. Set the initial parameters for the factory.
    1. Set the Velocity to 'fixed' and click the icon to set the velocity as follows:




    2. Ensure that the Charge is set to 'fixed' and then click the icon.
    3. Set the Charge to -1 nC.

Define the Environment

The final step in setting up the screw auger model is to set the domain of the simulation.

To define the environment:
  1. Select Environment in the Creator Tree.
  2. To prevent particles from leaving the domain in the Y-axis, expand the Environment section and select Boundary Conditions.
  3. In the Periodic Boundaries section, select the Y: checkbox .
Next Step - Run the Simulation