ASCEND

What ASCEND is

ASCEND is free desktop software for engineers and scientists who need to solve systems of equations. It lets users build complex models from simpler submodels using a purpose-built modeling language. It can handle nonlinear equations, linear and nonlinear optimization problems, and dynamic systems expressed as differential/algebraic equations. The graphical interface loads models, lets users choose a solver or integrator, and provides a view of how the model is solved. ASCEND handles measurement units and conversions, including inches, feet, centimeters, meters, and kilometers. Its thermodynamics capabilities cover distillation and flash problems and include IAPWS-IF97 steam tables. The software exposes its interface through C, C++, and Python, and Python scripts can automate loading and solving models. External libraries can add solvers, integrators, methods, relations, and import handlers; users can also write external methods in Python. ASCEND is released under the General Public License, and the homepage identifies version 0.9.8 as current. The site invites users to report bugs, contact the team, and contribute models or other work.