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Programming Guide
The EDEM Programming Guide describes the EDEM API.

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.
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.
- Define the EDEM Simulation Sequence
  Depending on where the UDL lies in the chain, each stage connects to the relevant UDL (if applicable) before performing its main function (such as calculating contacts).
- EDEM API Files
  EDEM includes the C++ EDEM API v3.9.0 for Contact Models, v2.2.0 for Factories, and v3.9.0 for Particle Body Forces.
- EDEM API Flags
  The EDEM API allows the author to enable or disable certain API functionalities through the use of flags in the setup function of either the Contact Model or Particle Body Force interface classes. As an API Author, you can use these flags to potentially save on memory or reduce processing time, as well as to prevent bugs or crashes caused by running with solvers or particle shapes that the API is not designed for. Flags are available for particle body force, contact models, solvers, and particle shapes.
- Contact Model User Defined Libraries
  A Contact Model UDL consists of a shared library file and, optionally, a file containing preferences. Using the EDEM API, you can write and compile a custom Contact Model as a User Defined Library (UDL) written in C/C++.
- Particle Body Force User Defined Libraries
  A Contact Model UDL consists of a shared library file and, optionally, a file containing preferences. Using the EDEM API, you can write and compile custom particle body forces as a User Defined Library (UDL) written in C/C++.
- Particle Factory User Defined Libraries
  A Particle Factory UDL consists of a shared library file and, optionally, a file containing preferences. Using the EDEM API, you can write and compile a custom Particle Factory for creating and initializing particles.
- Custom Properties
  A Custom Property is a named group of one or more numeric (double precision floating point) values with an associated unit type.
- API GUI Guide
  You can seamlessly integrate contact model and particle body force API plug-ins into EDEM. This allows changes to be made to plug-in parameters through the EDEM GUI, similar to any of the built-in Physics models.
- Compile API Models to Libraries
  A Third-party compiler allows you to compile C++ code to a library (.dll in Windows or .so in Linux).
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.

Programming Guide

The EDEM Programming Guide describes the EDEM API.

You can use the EDEM API to code and implement your own contact Physics, external couplings and particle-generation factories in the form of a User Defined Library (UDL). This UDL operates as a plugin to EDEM. For more information, see the API Reference help included in the EDEM installation folder.

When using the EDEM API, all units are SI.

User Defined Library Contact Model

A User Defined Library (UDL) is a custom library that you can write to define your own Physics models.

The following high-level sequence of the steps to write and use a UDL contact model are as follows:

The programmer typically adapts an existing contact model source file (available from the Altair Community) using a development environment or editor. Once compiled, the new contact model is loaded into EDEM for use in simulations.

Note: The same steps apply to both Particle Body Force and Particle Factory UDLs.