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 Acceleration to deg/s2
      • Angular velocity to deg/s
      • Length to mm
      • Mass to kg
      • Mass Flow Rate to kg/s
    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 (Conveyor Model).
    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 a bulk material, particle shapes, and their associated interaction properties.

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 'rock' in the Material highlighted field. Alternatively, you can also use the icons in the Toolbar.
  2. Define the bulk material properties.
    1. Select rock in the Bulk Material section.


    2. In the rock 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 rock from the dropdown list to define the interaction between all elements made of the material 'rock'.
    3. Specify the coefficients as follows:


  4. Create a new particle shape after defining the bulk material and interaction properties.
    1. Right-click rock in the Bulk Material section and then select Add Particle > Add Multi-Sphere.
    2. Enter the name 'rock 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: Multi-Sphere particles are made up of one or more spheres. In this tutorial, we are going to import a CAD template of a rock and fit four spheres to the template shape.
    1. In the right-hand corner, in the Templates section, click Edit....
    2. In the Import dialog box, click Import... and navigate to the folder that contains the mesh file that will be used as the template.
    3. In the Import Options dialog box, specify the units of measurement to Millimeters (mm).
    4. In the Mesh Control type ensure that all the settings have the default values and then click OK.
      Note: In this lesson, we are importing the particle template rock_particle.stl. The STL file format is already meshed, and changing the meshing options does not impact the mesh of the imported template. For other file formats such as STEP or IGES, you can modify the Geometry/template mesh by changing the element size options in the Import dialog box.
    5. Click the icon.
    6. Rename the template to Rock Template, and then click OK.
    7. On the right-hand corner, in the Templates section, select Rock Template from the Display Templates dropdown list.


    8. In the Creator Tree, select the rock particle and then select Modify Shape in the Detailed View section.
    9. Select Single Sphere from the Shape Library as follows:


    10. In the rock particle Spheres section, under the Viewer, change the Physical Radius of the sphere from 1 to 18 mm and the Position X, Y, Z to (0, -3, 0) mm.
    11. Add another sphere to the particle shape by right-clicking the rock particle Spheres table and then selecting Add Sphere.

    12. Set the radius of this new sphere (sphere 1) to 18 mm and the Position X, Y, Z to (-13, 0, 0) mm.
    13. With one of the spheres selected from the table in the Rock Particles Spheres section, click the Highlight Sphere icon in the View menu to distinguish the spheres.


    14. Add two more spheres and set their positions and radii as follows:




    15. In the rock particle Properties section, select Imported Template and then click Calculate Properties.
      Note:
      • When using the Imported Template option, the mass, volume, and moments of inertia are calculated from the CAD template.
      • Alternatively, you can use the Spheres option to calculate these properties from a collective assembly of spheres.
      • An automated way to generate spheres to fill a template is outlined in the following section. It is recommended in this tutorial to use the manually created four-sphere particle.
  6. Specify the size distribution of the bulk material.
    1. Expand the rock particle section in the Creator Tree and then select Size Distribution.
    2. In the Size Distribution section, select user-defined from the dropdown list.
    3. In the Scale By section, select Radius.
    4. Right-click the User Defined Size Distribution Parameters table and select Add three times.
    5. Specify the distribution parameters as follows:


Generate Particles from a Template

When defining the Bulk Material, you specify the positions of the particles in the template. You can use the alternative option of generating particles from a template.

To generate particles from a template:
  1. Select Bulk Material and then select Add Bulk Material in the Creator.
  2. Select the new Bulk Material and then right-click Add Shape from Library > Single Sphere.
  3. Click Edit... next to the Select Template dropdown list and import the CAD template (if not already imported).
  4. Use the following settings for the grid cells and sphere radius and click Generate Particle:


    EDEM then automatically generates the particle shape. These settings create approximately ten spheres that fill the template with the higher fidelity model shown on the left and the manually created four-sphere template on the right.


Define the Equipment Material

The next step in setting up the model is to add the equipment material that 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 and enter the name 'steel' in the highlighted field.
  2. Define the equipment material properties.
    1. Select steel in the Equipment Material section.
    2. In the steel Properties dialog box, 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 rock from the dropdown list to define the interaction between elements made of 'rock' and elements made of 'steel'.
    3. Specify the coefficients as follows:


Define the Geometries

The next step in setting up the model is to define the conveyor and factory Geometries used in the model.

To define the Geometries:
  1. Import the conveyor Geometry that has already been created and is ready to be imported into EDEM.
    1. Right-click Geometries in the Creator Tree and then select Import Geometry.
    2. Navigate to the file conveyor_hopper.stl and import it.
    3. In the Geometry Import Parameters dialog box, set Choose Units to Millimeters.
    4. Ensure that the Merge Sections checkbox is not selected and that all the mesh settings have the default values.
    5. Click OK.
    6. Select and right-click or press F2 to rename each section appropriately as follows:
      • belt
      • hopper
      • lower hopper
      • guide_1
      • guide_2
  2. Specify the conveyor kinematics.
    1. Select belt in the Creator Tree Geometries section.
    2. Right-click and then select Add Motion > Add Conveyor Translation (New Motion 1) and set up the Specification properties as follows:


      This creates an acceleration of 1 m/s2 between 1 and 3 s of simulation time.

    3. Right-click belt to add a second Conveyor Translation (New Motion 2) and set up the second motion as follows:


      Note: The second motion is set to have a constant velocity of 2 m/s starting at 3 s. The motion of the belt is defined by the Start and End points. In this case, the values have been input manually. However, you can also use the Pick tool to pick a Start and End point values. The Display Vector checkbox, if selected, shows the direction of the selected motion in the Viewer.


  3. Create the particle factory plate.
    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 > Polygon and then enter the name 'factory_plate' into the highlighted field.
    3. Select the polygon 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_plate in the Creator Tree and select the Transform subsection.
    5. Set the position as follows:


    6. Select the Polygon subsection and specify the Number of Edges and Dimensions of the polygon as follows:


  4. Create the particle factory.
    1. Right-click factory_plate in the Creator Tree.
    2. Click Add Factory and select Dynamic Factory.
    3. Select the newly created factory and ensure that the Factory Type is set to 'dynamic'. If not, right-click the new factory in the Creator Tree and then select Change Factory Type.
    4. In the Particle Generation section, select Total Mass and set the value to 500 kg.
    5. In the Generation Rate section, select Target Mass and set the rate to 50 kg/sec.
  5. Set the initial parameters for the factory.
    1. In the Parameters section, ensure that you have selected 'rock' from the Material dropdown list.
    2. Set the Position to 'random' to ensure that the particles are randomly created over the entire area of the plate.
    3. Set the Velocity to fixed and click the icon to set the velocity in the z-direction to -2 m/s.
    4. Select File > Save.

Define the Environment

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

To define the environment:
  1. Select Environment in the Creator Tree.
  2. Ensure that the Auto Update from Geometry checkbox is selected.
    Note: This automatically sets the domain of the simulation depending on the Geometries present. Set the Domain Properties as follows:


  3. Set the gravity.
    1. In the Gravity section of the Detailed View, ensure that the gravity is set to -9.81m/s2 in the z-direction.
Next Step - Run the Simulation