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Tutorials
Start using EDEM with our interactive tutorials.
API Tutorials
These tutorials are intended for users who are looking to get started with EDEM API models that they have previously created, or downloaded from the Altair Community.
EDEM API 4100 Variable Cohesion
This tutorial describes how to create a new cohesion contact model, based on an existing contact model supplied with EDEM.
Create the New Cohesion Physics
The nest step is to add the Time Factor and create the library file (64 bit) to create the new cohesion Physics.

Welcome
What's New
This section describes the key features in EDEM version 2025.1.
About EDEM
EDEM is a high-performance simulation software for bulk and granular materials.
Hardware Requirements
This section details the minimum system requirements and requisites for running EDEM.
Release Notes EDEM 2025.1.1
This section contains information about the EDEM 2025.1.1 release, such as bug fixes.
Release Notes EDEM 2025.1
This section contains information about the EDEM 2025.1 release, such as key features, enhancements, and bug fixes.
Tutorials
Start using EDEM with our interactive tutorials.
- Introduction to EDEM Tutorials
  These introductory tutorials are intended for users who are new to EDEM, and want to get started with the fundamentals of setting up, running, and analyzing a simulation.
- Physics Models Tutorials
  These tutorials are intended for users who are new to the EDEM contact models (physics behavior of particle/Geometry elements when they come into contact with each other) and describes how to use the appropriate contact models.
- Application Tutorials
  These tutorials are intended to cover specific applications, or application-focused features of EDEM. They are primarily intended for users working in the relevant application areas, but may also be useful for new users intending to understand the areas where EDEM can be deployed.
- API Tutorials
  These tutorials are intended for users who are looking to get started with EDEM API models that they have previously created, or downloaded from the Altair Community.
  - EDEM API 4000 Particle Replacement
    This tutorial describes how to add an existing API model to a simulation which includes Bonded Particles. The API model replaces large spheres with clumps of smaller spheres.
  - EDEM API 4100 Variable Cohesion
    This tutorial describes how to create a new cohesion contact model, based on an existing contact model supplied with EDEM.
    - Create and set up the Project
      You must first create and compile the new project and in Visual Studio 2019 For Windows Desktop
    - Add Source files to the Project
      The next step is add source files to the project that you have created.
    - Create the New Cohesion Physics
      The nest step is to add the Time Factor and create the library file (64 bit) to create the new cohesion Physics.
    - EDEM Creator - Use the Linear Cohesion API Model
      Learn how to load an existing simulation model using EDEM Creator.
    - EDEM Simulator - Run the Simulation
      Once you have set up the model, learn how to run fast and efficient simulations using EDEM Simulator.
    - EDEM Analyst - Review the Simulation
      The final step in this tutorial is to learn how to review, examine, and verify the changing behavior of the particles over time..
    - Create a Cohesion Model on Linux
      This section describes how to create a new cohesion contact model on Linux. To complete this tutorial on Linux instead of Windows, the library file which is loaded into EDEM must be compiled as a.so (shared-object) file instead of a .dll file.
Get Started with EDEM
The EDEM user interface comprises three icons for each simulation component - Creator, Simulator, and Analyst.
EDEM Creator
EDEM Creator is the pre-processor for creating an EDEM simulation model, including setting up equipment and defining the generation of bulk materials.
EDEM Simulator
EDEM Simulator is a powerful solver used for fast and efficient simulations.
EDEM Analyst
EDEM Analyst is the post-processor used to analyze and visualize the results of your simulation.
EDEM Physics Models
A Contact Model describes how elements behave when they come into contact with each other.
EDEM Cal Utility
EDEM Cal is a utility which works with EDEM and is designed to assist in performing calibration.
EDEM Calibration Kits
The EDEM Calibration kits are a collection of EDEM models of standard bulk solids characterization tests commonly used for EDEM material model calibration.
GPU CUDA Guide
The EDEM CUDA GPU module uses the latest General Purpose Computing on Graphical Processing Units (GPU) technology.
Programming Guide
The EDEM Programming Guide describes the EDEM API.
Coupling Interface Programming Guide
The Coupling Interface Programming Guide provides an overview of how to use the EDEM Coupling Interface to couple with a generic CFD code and/or Multi Body dynamics codes.
EDEMpy
EDEMpy is a Python library for accessing EDEM data from .h5 files (the underlying EDEM file format). EDEMpy does not require prior knowledge of advanced programming.
EDEM Solver Capabilities
EDEM contains four solver engines.
Appendix
This section provides additional information about how to estimate simulation time, supported EDEM File types, attribute definitions, and so on.
EDEM Terminology
Definitions of terms used in EDEM.
References and Bibliography
This section cites the contributions made by various authors and sources that have been used as reference material for EDEM, and the specifics of how they have been applied can be found in the individual contact model sections.

Create the New Cohesion Physics

The nest step is to add the Time Factor and create the library file (64 bit) to create the new cohesion Physics.

To create the new cohesion Physics:

Add the Time Factor.
1. In the Visual Studio Solution Explorer dialog box, double-click CVariableCohesion_v3_7_0.cpp.
2. Press Ctrl + F to search for contactResults.normalForce.
  This indicates the end of the Physics section where the Vector F_cohesive is added to the Normal Force of the contact. Cohesion is calculated from the energy density values (nCohesiveFactor) multiplied by the overlap area (nArea).
3. Locate the F_cohesive vector in the source file as follows:
4. Add the multiplying factor of the current simulation time to the F_cohesive calculation as follows:
  Create a new double called cohesion_time before the F_cohesive calculation and assign this as the value of the current simulation time:
5. Add a limit of 0 - 3 s for the cohesion increase to take place and update the code as follows:
  
  Note: Multiplying by time causes an error where, after a large time has elapsed (60 s), the cohesion value will have increased accordingly, and could be unexpectedly high as the cohesive force increase does not have any limitations.
6. Save the file.
Create the .dll library file (64 bit).
1. Go to Build > Configuration manager.
2. In the Active Solution Platform, select Release and x64.
  You can run this simulation with the Debug or Release .dlls. It is usually recommended to test the simulation in the Debug mode and run the simulation using the Release mode once the model is finalized, as the Release mode is significantly faster to compute.
3. Select Build > Build Solution to compile the model.
  Note:
  - If compilation is successful, the Output window in Visual Studio will display “Build: 1 succeeded”, along with the location of the newly created *.dll file.
  - If the build fails, additional information is displayed to explain build failure. It is recommended to always start with the first error message in the list as it may be the reason for subsequent errors.
4. Copy the newly created .dll file to the same location as the cohesion_input.dem file which is included with the tutorial files.
5. Copy and paste the cohesion_prefsV2.txt file into the same location.