Particle Replacement Tutorial.docx

1、Particle Replacement TutorialEDEM Tutorial:Bonded ParticlesNote this tutorial uses the EDEM v1.1 legacy APIIntroductionThis tutorial describes how to create a simulation that uses EDEMs bonded particle model. The model also uses custom factories and a particle body force.(1)(2)(3)(4)(1) Solid sphere

2、s are created and allowed to settle. (2) The large particles are replaced with bonded meta-particles. (3) The bonded meta-particles are damaged in the mill, and (4) eventually breakup.1. Start EDEM then go to File Save As2. Select a working directory on the local machine (e.g. “C:EDEM_Tutorials”).3.

3、 Enter a file name (e.g. “Bonded_Tutorial.dem”) and click Save.4. Copy the following tutorial files to your working directory:ParticleReplacement.dllParticle_Replacement_prefs.txt Particle_Cluster_Data.txtEDEM Creator: Setting up the model Step 1: Set the Global Model ParametersChoose the unitsThe f

4、irst step in creating the model is to set the units used throughout EDEM. 1. Go to the Options Units menu.2. Change the following measurement units: Angular velocity to rpm Length to mmEnter the model title and descriptionThe model title and description will appear in the Data Browser window. 1. Cli

5、ck on the Globals tab in the Tabs pane. 2. Enter the title Grinding mill simulation involving the bonded particle model in the Title field in the Simulation section.Edit the file locationsSet the EDEM file locations to read the custom libraries you copied to your working directory:1. Browse to Optio

6、ns File Locations. 2. Set the directory for Particle Body Force and Factories to your working directory.Set the gravity and define the materials1. Be sure gravity is set to -9.81 m/s2 in the Z direction.2. In the Materials section, click the Transfer button to open the Material/Interactions Transfer

7、 dialog.3. Transfer High-stiffness from the materials database to your simulation.4. Click OK then rename the material as steel.5. Click the + button at the top of the Materials section. This creates a new material.6. Highlight the material and change its name to particle.7. Set the Poissons ratio,

8、Shear modulus, and density as shown below:Define the interactions between the materials1. Select particle from the drop-down list at the top of the materials section.2. Click the + button in the Interaction section. Select particle when prompted.3. Set the coefficients as follows:4. Add an interacti

9、on for steel with coefficients as follows:Step 2: Define the ParticlesCreate first particle type1. Click on the Particle tab in the Tabs pane. 2. Click the + button and type a name 10mm_spheres in the Name field.3. Set the radius of the surface to 10 mm.1. Set the material to particle.2. Click the C

10、alculate Properties button and pick the Surfaces option.Create second particle type1. Click the new particle + button again and type a name Fraction.2. Set the radius of the surface to 3 mm.3. Set the contact radius to 4 mm.3. Set the material to particle.4. Click the Calculate Properties button and

11、 pick the Surfaces option.Create third particle type1. Click the new particle + button again and type a name Whole.2. Set the radius of the surface to 20 mm.5. Set the material to particle.6. Click the Calculate Properties button and pick the Surfaces option.Step 3: Set the physics models1. Select P

12、article to Particle from the Interaction pulldown in the Physics section.2. Select Hertz-Mindlin (no slip) then click the x button to remove it.3. Click the + button then select the Hertz-Mindlin with Bonding built-in model:4. Click the configure buttonto define the bond.5. Add a Fraction + Fraction

13、 active bond then set the parameters as follows:6. Select Particle to Geometry from the Interaction pulldown.7. Select Hertz-Mindlin (no slip) then click the x button to remove it.8. Click the + button then select the Hertz-Mindlin with Bonding built-in model.Particles do not become bonded to the ge

14、ometry when using the Hertz-Mindlin with Bonding model: adding a particle-geometry interaction ensures the difference between physical and contact radius is taken into account.9. Select Particle Body Force from the interaction pulldown then choose ParticleReplacement:Step 4: Define the Domain and Ge

15、ometryImport the mill geometryThe mill geometry has been created in a CAD package ready for import.1. Click on the Geometry tab in the Tabs pane.2. Click the Import button in the Sections section.3. Navigate to the file grinding_mill.stp and import it.4. When the Geometry Import Parameters dialog ap

16、pears leave all the settings at the default values and click OK.5. When prompted, set the units of measurement to Milimetres (mm).6. Rename the geometry to mill and set the material to steel.Configure the dynamics1. Select the mill then click the Dynamics tab.2. Create a new linear rotation dynamic

17、as follows:Create the particle factory geometry1. Click the Geometry tab.2. Click the + button to create a new cylinder called factory.3. Click on the polygon tab and set the specification as follows:4. Click on the Details tab and set the type to virtual.Create the outer cylinder1. Click the Geomet

18、ry tab.2. Click the + button to create a new cylinder called outer_walls.3. Click on the cylinder tab and set the specification as follows:4. Click on the Details tab and set the type to physical and material to steel.Step 5: Create the Particle FactoriesCreate two particle factories one for each ty

19、pe of particle.Create the first particle factory1. Click on the Factories tab.2. Click the + button to create New Factory 1.3. Set factory type to static.4. Select Create 3 particles.Set the factorys initial conditions1. Be sure New Factory 1 is selected in the Section pulldown.2. Set the Type to fi

20、xed and select Whole.3. Set the Z velocity to -1.0 m/s.Create the second particle factory1. Click the + button again to create New Factory 2.2. Set factory type to static.3. Select Create 100 particles.Set the factorys initial conditions1. Be sure New Factory 2 is selected in the Section pulldown.2.

21、 Set the Type to fixed and select 10mm_spheres.3. Set the Z velocity to -1.0 m/s.Add the custom factorySelect Transfer and choose ParticleReplacement. (or ParticleReplacementx64)The custom factory has already been written and compiled. The Particle Body Force part of the factory removes all particle

22、s called Whole at a set point in time and replaces them with a meta-particle made from a number particles of type Fraction. Single sphere particle replaced with a multi sphere meta-particleSettings for the factory are defined in the file Particle_Replacement_prefs.txt.The positions of the individual

23、 spheres within the meta-particle are controlled by the file Particle_Cluster_Data.txt.EDEM Simulator: Run the SimulationStep 1: Set the Time OptionsSet the time step1. Click on the Simulator button:2. Set the fixed time step to 20%. (2.0e-05)Set the simulation time and grid optionsThe simulation ti

24、me is the amount of real time your simulation represents. 1. Set the total simulation time to 5s.2. Set the Target Save Interval to 0.005s.3. Set the grid size to 6 Rmin.Step 2: Run the Simulation1. Click the Start progress button at the bottom of the simulation window.2. Click the Refresh Viewer bu

25、tton at any point to update the Viewer and see how the simulation is progressing. EDEM Analyst: Analyzing Your ResultsStep 1: Configuring the DisplayConfigure the geometry1. Switch to the Analyst and click the Model tab.2. Reduce the opacity of the Mill to 0.8 then click Apply.3. Select Factory, de-

26、select display, then click Apply.4. Select outer_walls, de-select display, then click Apply.Step 2: Coloring Elements1. Click the Coloring tab.2. Select a unique color for the particle types Whole, Fraction and 10mm_sphere.3. Click the Play button to watch the particle break-up in progress.Step 3: Graphing Bonds1. Switch to the graphing tool then click the Line Graph tab.2. Leave the X axis as time and set the remaining options as follows:3. Click Create Graph to create the graph: