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Programming Guide
The EDEM Programming Guide describes the EDEM API.
Custom Properties
A Custom Property is a named group of one or more numeric (double precision floating point) values with an associated unit type.

Welcome
About EDEM
EDEM is a high-performance simulation software for bulk and granular materials.
What's New
New features and enhancements available in EDEM.
Release Notes
This section contains information about the EDEM release, such as key features, enhancements, bug fixes, and known issues.
Tutorials
Start using EDEM functionality 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 Contact 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.
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.
- User Defined Library Contact Model
  A User Defined Library (UDL) is a custom library that you can write to define your own Physics models.
- 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 v3.3.0 for Contact Models, v2.1.0 for Factories, and v3.3.0 for Particle Body Forces.
- 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.
  - Define Custom Properties
    You can define any number of custom properties.
- 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.

Custom Properties

A Custom Property is a named group of one or more numeric (double precision floating point) values with an associated unit type.

Custom properties allows you to dynamically define custom attributes for use in your simulation.


Custom Property	Example
Contact	Contact duration, highest force during contact
Geometry	Cumulative impact force, wear
Particle	Residence time, temperature
Simulation	Stickiness of a surface

Custom properties store additional attributes (for example, contact duration) for further post-processing. You can plot or export Custom properties, similar to any other attribute. When loaded, contact models, particle body forces, and coupled applications can all use and share data about these new custom properties.


Attribute	Description
Name	Indicates the unique name of the custom property.
State	When you first add properties, they are defined as tentative. Tentative properties do not have space allocated for them. When simulation starts, tentative properties are finalized and space is allocated for them.
Storage Type	Indicates the properties data type (currently always a C++ double).
Number of elements	Indicates the number of elements. Usually a property has one element. A property with a position in 3D space would have three elements (X, Y, and Z).
Units	Indicates the unit type. For example, length, temperature, charge, velocity, and so on. If the property has no unit, this is set to 'None'.
Values	Indicates the initial values of the property. Double-click to change the value (provided the custom property is either still tentative or is a simulation property). For custom simulation properties, the Values section also indicates the value for the current Time Step.

Any UDL that uses a custom property with the same name and category will share the property’s value(s) and have the ability to manipulate them, provided the two UDL definitions (name, units, number of elements, and data type) are identical. If two UDLs have different definitions, only the first UDL will load. The second UDL will not load and an error is displayed.

You can call the Value of a custom property and modify the Delta of a custom property. At the end of a simulation cycle, the Delta is added to the Value, and the Value is updated accordingly for the next Time Step .