DWSIM is an open-source CAPE-OPEN compliant chemical process simulator for Windows and Linux. Built on the top of the Microsoft .NET 4.0 and Mono Platforms and featuring a rich Graphical User Interface, DWSIM allows chemical engineering students and chemical engineers to better understand the behavior of their chemical systems by using rigorous thermodynamic and unit operations' models with no cost at all. Since DWSIM is open source, they can see how the calculations are actually being done by inspecting the code behind during execution using free tools available elsewhere.

DWSIM has an easy-to-use graphical interface with many features: CAPE-OPEN features: Thermo 1.0/1.1 Property Package Socket, Thermo 1.1 Property Package Server, Unit Operation Socket and Flowsheet Monitoring Object support. Additionally, DWSIM exposes its IronPython/IronRuby Script (Custom) Unit Operation for all CAPE-OPEN compliant simulators.

Thermodynamic models: PC-SAFT, FPROPS, CoolProp, Peng-Robinson, Soave-Redlich-Kwong, Lee-Kesler, Lee-Kesler-Plöcker, UNIFAC, Modified UNIFAC (Dortmund), UNIQUAC, NRTL, COSMO-SAC, LIQUAC*, Extended UNIQUAC, Chao-Seader, Grayson-Streed, Raoult's Law, IAPWS-IF97 Steam Tables, IAPWS-08 Seawater, Black-Oil and Sour Water;

Unit Operations: Mixer, Splitter, Separator, Pump, Compressor, Expander, Heater, Cooler, Valve, Pipe Segment, Shortcut Column, Heat Exchanger, Reactors, Component Separator, Orifice Plate, Distillation/Absorption Columns, Solids Separator, Cake Filter, Excel, Script and Flowsheet Unit Operation;

Utilities: Phase Envelope, Hydrate Calculations, Pure Component Properties, Critical Point, PSV Sizing, Vessel Sizing, Spreadsheet and Petroleum Cold Flow Properties;

Tools: Binary Data Regression, Compound Creator, Bulk C7+ and Distillation Curves Petroleum Characterization and Reactions Manager;

Process Analysis: Multivariate Constrained Optimization and Sensitivity Analysis utility; Extras: Scripting System and Plugins Interface