MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
EMSO simulator - EMSO simulator is an equation-oriented process simulator with a graphical interface for modeling...
FreeCAD - An open-source parametric 3D modeler
StochSD - StochSD (Stochastic System Dynamics) is a Continuous System Simulation extension that is built with the capabilities to help you simulate continuous flows between compartments and, most importantly, also has the power to manage discrete transitions …
Altair Activate - Altair Activate is an open & flexible tool for rapidly modeling and simulating products as multi-disciplinary systems in the form of 1D models (expressed as signal-based or physical block diagrams), optionally coupled to 3D models.