AUDYSIM™ Simulation Model Software Package

AUDYSIM™ is a rigorous, real-time, high fidelity process modeling architecture that operates over the full range of operating conditions. Models are developed based upon “First Principles of Chemical Engineering” using accurate thermodynamic properties and equipment performance design data. The model software utilizes a structural simulation development language C++ or C#. In addition, Utilities for configuring the Instructor Station displays (FODs, malfunctions, etc.), ESD Panel Displays, and configuring I/O to the Operator Station DCS are provided to allow full simulation software maintenance capabilities.


In addition to their use in Operator Training Simulators, AUDYSIM™ Simulation Models can also be used for engineering studies or for advanced process control applications.  With the AUDYSIM™ Maintenance Package, the Client will have the ability to use the models to:

  • Design and test control systems
  • Evaluate potential changes to control systems
  • Conduct "What if" studies for equipment malfunctions or other failure conditions in order to develop plant operating strategies
  • Analyze the effects of process modifications
  • Test and validate ESD/interlock systems

AUDYSIM™ Simulation Models developed for engineering studies can be integrated with the process control system to provide calculations for DCS based advanced process controls, or they may be used as the front end driver for a multivariable controller for closed loop advanced process control.

Modular Structure

The modules are themselves rigorous dynamic models - standard and pretested. These algorithms are supported by a thermodynamics package. An extensive library of unit operations, equipment types, control functions, and other algorithms has already been developed. Model development is thereby simplified. Because the algorithms have been extensively tested, the Engineer can have a high degree of confidence that they will perform properly, without need of retesting on each project. And, no realistic size limitation exists for a Simulation Model. In addition to library modules, custom modules or models, can be integrated into the respective Simulator System.

AUDYSIM™ Models are based on a "First Principles of Chemical Engineering" approach (conservation of mass and energy), thermodynamic properties, and equipment performance/design data. Each piece of plant equipment is represented by differential and algebraic (linear and non-linear) equations to ensure that individual unit responses as well as complex unit interactions are preserved, thus providing high overall fidelity of the model.

Operator Station Configuration Utilities

A separate utility will be provided and is used for configuring the Operator Station. A graphic conversion utility will be provided which will translate the Yokogawa DCS graphics to emulated graphics for the Operator Station.

Field Operator Station Configuration Utilities

This functionality is actually a subset of the Instructor Station Configuration File Utility.

Software Architecture

The Simulation Models are written in a high level software language (C++ and/or C#) so that the Process Simulation Models can be easily established. Complex programming is not required with AUDYSIM™. AUDYSIM™ design ensures that data transmission and reception are performed quickly. This is vital for response time when integrating to actual or emulated distributed control systems (DCSs) and for connecting to additional hardware and/or software system.

The structured software package which is completely modular and flexible consisting of the following major sections:

  • Simulation Database
  • Simulation Executive
  • Simulation Models User Library
  • Debugging Capability
  • Configuration Utilities

Library Modules

Library modules are typically equipment, unit operation and functional modules. Modules that simulate unit operations include: compressors, distillation sections, drivers, heat exchangers, pumps, valves, and vessels. Some modules provide structural functions for the model, such as: mix points, pressure nodes, etc. Other modules provide instrumentation and logic functionality: control processors, level transmitter and compressor surge controller.

Instructor Station Configuration Utility

A separate utility is also provided along with AUDYSIM™ to allow configuration of the Instructor Station. Instructor Station Configurations are contained in an ASCII file which can easily be modified using a text editor. As part of the utility, the file is checked for errors prior to loading into the Instructor Station database.

A Graphics Conversion Utility is also provided which will translate the Yokogawa DCS graphics into the proper Instructor Station graphics format.

A similar utility is provided for configuring the ESD/Panel Operator Station displays.