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EDEM Tutorial
EDEM-Fluent: Two-phase Eulerian simulation
EDEM-FLUENT Tutorial: Two-Phase Eulerian Simulation
Introduction
This tutorial describes how to set-up a coupled 2-phase EDEM-Fluent simulation. The
model shows a rectangular intersection in a pipe. This is an example of a Eulerian-
Eulerian simulation, which also uses the Dense Discrete Particle Model. This tutorial
assumes you have some experience of using Fluent. This tutorial also assumes the
use of Fluent version 17.1, so some of the steps may differ from those presented here
if you are using a different version.
To begin with, with we create a particle bed in EDEM:
1. Start EDEM.
2. Go to File > Save As…
3. Select a location on the local machine (e.g. “C:\EDEM_Tutorials”).
4. Enter a file name (e.g. “Packed_bed.dem”) and click Save.
EDEM Creator: Setting up the model
Step 1: Define the Project and Settings
Choose the units
The first step in creating the model is to set the units used throughout EDEM.
1. Go to Tools > Options > Units, and set the following measurement units:
▪ Length: mm
▪ Velocity: m/s
Enter the model title and description
1. Click on Project in the Creator Tree and set the simulation title to Two-Phase
Eulerian Simulation. Enter a description in the Description field.
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EDEM-FLUENT Tutorial: Two-Phase Eulerian Simulation
Step 2: Define the Bulk Material
1. Create a new Bulk Material called Particle with the following properties:
2. Add the interaction between elements made of Particle and leave the coefficients
as default.
3. Create a new particle of the Particle material called Particle.
4. Change the shape of the particle to be Dual Sphere.
5. Change the radius of sphere 0 to 2mm, and set the Position X to be -0.5 mm.
6. Change the radius of sphere 1 to 2mm, and set the Position X to be 0.5 mm.
7. Click the Calculate Properties button and pick the Spheres option.
The volume of these particles lies within the maximum and minimum mesh volume.
Some cells will be filled to the maximum fill volume with the solid phase, significantly
affecting the fluid flow. Consequently, the simulation is to be run using an Eulerian-
Eulerian approach.
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EDEM-FLUENT Tutorial: Two-Phase Eulerian Simulation
Step 3: Define the Equipment Material
Add and define a new equipment material
1. Create an Equipment Material called Geometry with the following properties:
Define the bulk material - equipment material interaction
1. Create the interaction between elements made of Particle and elements made of
Geometry and leave the default coefficients.
Step 4: Define the Geometry
Import the geometry
The geometry has already been created and is ready to be imported into EDEM and
Fluent.
The mesh file contains three sections: the geometry walls, a velocity inlet, and a
pressure outlet. Only the walls are imported.
1. Right click on Geometries tab in the Creator Tree.
2. Select Import Geometry...
3. Navigate to the file intersection_vertical.msh and click Open.
4. When prompted, set the units of measurement to Meters. Leave the Geometry
Import Parameters options at their defaults and click OK.
Create the particle factory plate
When running two-phase simulations, the factory must be inside the geometry. If the
factory is on the domain boundary (in other words, z is set to 0) the particles will be
created on that boundary. In EDEM this is not a problem however Fluent will see a
section of the particle out of the domain and will attempt to find a mesh cell to contain
the volume. This results in a slow simulation.
1. Right click on Geometries tab in the Creator Tree, hover over Add Geometry and
select Polygon.
2. Rename the section factory.
3. Set the type to virtual.
4. Expand factory in the Creator Tree and select Polygon.
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EDEM-FLUENT Tutorial: Two-Phase Eulerian Simulation
5. Set the size parameters as follows:
Create the particle factory and set its properties
1. Right click on factory in the creator tree and select Add Factory.
2. Select Unlimited Number, in the Particle Generation section.
3. Set the Generation Rate to 2500
4. Set the Velocity to fixed and click the button.
5. Set the z velocity to 5 m/s and click OK.
Step 5: Define the Physics
Set the Contact Models
1. For the Particle to Particle and Particle to Geometry Interactions, check that the
Hertz-Mindlin (no slip) contact model is being used.
Step 6: Define the Environment
Set the acceleration due to gravity and domain
1. Check that Gravity is set to -9.81 m/s
2
in the z direction.
2. In the Domain section, leave the Auto-update option checked.
3. Select File > Save. Next we move onto the EDEM Simulator to start processing the
simulation.
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