Review of open source process simulators It is not always necessary to use only expensive simulation packages

Review of open source process simulators

One of the most important reasons that process simulation is not used more across the industry is the price of the simulation packages. Some of those most used software packages come together with the price reaching tens of thousands of USD for one license. Although, this price can be easily justified with the benefits achieved, it still very often remains an obstacle, especially for small engineering companies. Thanks to the hard-working and generous groups of experts who share their knowledge with all of us, this article presents some of the available open source process simulators. However, they are not allowed to be used commercially.



DWSIM is a software for modeling, simulation, and optimization of steady-state chemical processes. It is the most popular open source simulation software that can be used for Windows, Linux and Mac OS X. It is written in Visual Basic and features a comprehensive set of unit operations, advanced thermodynamic models, support for reacting systems, petroleum characterization tools, and a fully-featured graphical interface. Definitely should be one of the solutions on the top of your list if you are new in the process simulation or would like to get the results for a less complex process problem. It has the great number of important features, most of those that we are used to from using standard simulator packages. Some of them are:

  • VLE, VLLE, SLE and Aqueous Electrolyte calculations using Equation of State, Activity Coefficient and Chao-Seader models,
  • Supports CAPE-OPEN Unit Operations and Thermo 1.0/1.1 Property Packages,
  • Exposes Property Packages as CAPE-OPEN 1.1 Thermodynamic Equilibrium and Property Calculators,
  • Supports ChemSep's Component Database and Column Model,
  • Process Flowsheet Diagram (PFD) Drawing Interface,
  • Rigorous Distillation/Absorption Column models,
  • Support for Chemical Reactions and Reactors,
  • Characterization of Petroleum Fractions using bulk properties and/or ASTM/TBP, distillation curves and creation of Hypothetical Components using UNIFAC groups,
  • Multivariate Optimization and Sensitivity Analysis utility,
  • Excel Interface for Thermodynamic Calculations,
  • Standalone Thermodynamics Library,
  • Component Creator Utility for user-defined components.

Until then, you can find out more about DWSIM here and download the software using this download link.

2. COCO simulator

The other process simulator that comes with the bunch of features is called COCO. Behind this exotic name is another free-of-charge process simulator, non-commercial, graphical, modular and CAPE-OPEN compliant simulator for steady-state and sequential simulation process modeling. It was originally intended as a test environment for CAPE-OPEN modeling tools but now provides a free chemical process simulation for students. It is an open flowsheet modeling environment allowing anyone to add new unit operations or thermodynamics packages.

A list of features includes:

  • Thermodynamics for Engineering Applications, 
  • the CAPE-OPEN Unit-operations Simple package is shipped with COCO. It contains a splitter, a mixer, heat exchangers, pumps and reactors amongst other unit operations. 
  • Reaction Numerics package.

The free package comes with certain limitations in calculations, such as limitation to 40 compounds, but can definitely be used for some simplified or short-cut modeling. What is especially beneficial is the collection of free sample flow sheets available for download at their web-site. Sample flow sheets include prepared examples such as:

  • Pressure swing azeotropic distillation of methanol and acetone,
  • Benzene-toluene-xylene divided wall column,
  • Methanol synthesis from syngas,
  • Combined heat and power cycle.

To download the software, follow this link.


OPENMODELICA is an open-source Modelica-based modeling and simulation environment intended for industrial and academic usage. Its long-term development is supported by a non-profit organization – the Open Source Modelica Consortium (OSMC). Modelica is not a process oriented simulator such as DWSIM, but a general modeling tool and the platform closer to Matlab.

OpenModelica is a comprehensive compilation and simulation environment based on free software distributed in binary and source code form for research, teaching, and industrial usage. 
There is a long list of industrial and university members including ABB, Siemens, Evonik etc.

Modeling using OpenModelica enables:

  • Multi-domain modeling
  • Hybrid modeling
  • Visual component modeling etc.

One example of how to use OpenModelica is ABB OPTIMAX® model that provides advanced model-based control products for power generation and water utilities. Plant models are typically formulated in Modelica and deployed through FMI 2.0. The optimizing control applications maximize the efficiency and provide more flexibility to large conventional power plants that face frequent load ramps and start-ups. Moreover, they aggregate small renewable units to large virtual power plants. This enables renewables to provide grid services like power/frequency control, achieving grid stability despite of high penetration of renewable power and raising revenues. ABB uses several compatible Modelica tools, including OpenModelica, depending on specific application needs. OpenModelica provides debugging features that help to save a lot of time during model development.

To download OpenModelica software, please follow this link.