Best Free Simulation Software

FEATool Multiphysics - "Physics Simulation Made Easy" - a fully integrated physics, FEA, and CFD simulation toolbox. FEATool Multiphysics is a fully integrated simulation platform with a unified interface for several Finite Element Analysis (FEA) and Computational Fluid Dynamics (CFD) multi-physics solvers, such as OpenFOAM, SU2 Code, and FEniCS. This uniquely allows for modeling coupled physics phenomena such as found in fluid flow, heat transfer, structural, electromagnetics, acoustics, and chemical engineering applications, within a single user-friendly interface. With these capabilities, FEATool Multiphysics has become trusted tool by engineers and researchers worldwide to accelerate innovation and quickly achieve results in the energy, automotive, semi-conductor, and process industries.

Based on computational physics, Energy2D is an interactive multiphysics simulation program that models all three modes of heat transfer, conduction, convection, and radiation, and their coupling with particle dynamics. Energy2D runs quickly on most computers and eliminates the switches among preprocessors, solvers, and postprocessors typically needed to perform computational fluid dynamics simulations. It allows you to design "computational experiments" to test a scientific hypothesis or solve an engineering problem without resorting to complex mathematics. Work is also underway to incorporate other types of energy transformations and support multiple types of fluids. The conduction part of Energy2D is highly accurate, but the convection and radiation parts are not 100% accurate. Hence, in cases that involve convection and radiation, Energy2D results should be considered qualitative. More than 40 scientific papers have used Energy2D as a research tool.

OpenModelica is an open source modeling and simulation environment based on the Modelica language, intended for industrial and academic use. Its development is supported by the Open Source Modelica Consortium (OSMC), a non-profit organization. The platform aims to provide a comprehensive Modelica modeling, compilation, and simulation environment distributed in both binary and source code forms for research, teaching, and industrial applications. OpenModelica supports the Modelica Standard Library and is compatible with various operating systems, including Windows, Linux, and macOS. It is designed to facilitate the development and execution of both low-level and high-level numerical algorithms, making it suitable for control system design, solving nonlinear equation systems, and developing optimization algorithms applied to complex applications. The platform also offers tools for debugging, visualization, and animation, enhancing the user experience in modeling and simulation tasks.

NVIDIA Isaac Sim is an open source reference robotics simulation application built on NVIDIA Omniverse, enabling developers to design, simulate, test, and train AI-driven robots in physically realistic virtual environments. It is built atop Universal Scene Description (OpenUSD), offering full extensibility so developers can create custom simulators or seamlessly integrate Isaac Sim's capabilities into existing validation pipelines. The platform supports three essential workflows; large-scale synthetic data generation for training foundation models with photorealistic rendering and automatic ground truth labeling; software-in-the-loop testing, which connects actual robot software with simulated hardware to validate control and perception systems; and robot learning through NVIDIA’s Isaac Lab, which accelerates training of behaviors in simulation before real-world deployment. Isaac Sim delivers GPU-accelerated physics (via NVIDIA PhysX) and RTX-enabled sensor simulation.

NVIDIA Isaac Lab is a GPU‑accelerated, open source robot learning framework built on top of Isaac Sim, designed to unify and simplify robotics research workflows such as reinforcement learning, imitation learning, and motion planning. It leverages realistic sensor and physics simulation to support accurate training of embodied agents, providing ready‑to‑use environments, spanning manipulators, quadrupeds, and humanoids—with support for 30+ benchmark tasks and integration with popular RL libraries like RL Games, Stable Baselines, RSL RL, and SKRL. Isaac Lab features a modular, configuration‑driven design that enables developers to easily create, modify, and scale learning environments; it also supports collecting demonstrations via peripherals (gamepads, keyboards) and allows custom actuator models to facilitate sim‑to‑real transfer. The framework is built for both local and cloud deployment, accommodating flexible scaling of compute resources.

WELSIM finite element analysis software helps engineers and researchers conduct simulation studies and prototype virtual products.

OpenFOAM is the free, open-source CFD software developed primarily by OpenCFD Ltd since 2004. It has a large user base across most areas of engineering and science, from both commercial and academic organizations. OpenFOAM has an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to acoustics, solid mechanics and electromagnetics. OpenFOAM is professionally released every six months to include customer-sponsored developments and contributions from the community. It is independently tested by ESI-OpenCFD's application specialists, development partners and selected customers, and supported by ESI's worldwide infrastructure, values and commitment. Quality assurance is based on rigorous testing. The process of code evaluation, verification and validation includes several hundred daily unit tests, a medium-sized test battery run on a weekly basis, and a large industry-based test battery-run.

DWSIM is a free and open source CAPE-OPEN compliant chemical process simulator that operates across multiple platforms, including Windows, Linux, macOS, Android, and iOS. It features an intuitive graphical user interface and offers capabilities previously exclusive to commercial simulators. DWSIM supports both steady-state and dynamic simulations, utilizing a parallel modular solver for efficient modeling. It includes advanced property packages. The simulator provides a comprehensive suite of unit operations, including mixers, splitters, separators, pumps, compressors, expanders, heaters, coolers, valves, pipe segments, shortcut columns, heat exchangers, various reactors, distillation and absorption columns, solids separators, cake filters, spreadsheets, Python scripts, and flowsheet unit operations. It also provides an Excel Add-In for performing thermodynamic calculations within spreadsheets and an automation API for creating, loading, modifying, running, and saving flowsheets.

SimFlow is a desktop Computational Fluid Dynamics (CFD) analysis software for Windows and Linux OS. It is based on OpenFOAM libraries, acting like an OpenFOAM GUI. It is a professional CAE package for engineers offering fully-featured 3D simulations. SimFlow is a powerful general-purpose CFD software. It combines an intuitive graphical user interface with the advantages of the open-source OpenFOAM® libraries. Download SimFlow and use it for free in an evaluation mode to solve the most complex problems you face as an engineer, scientist or student. Maybe you use CFD software on a daily basis or maybe just want to start your adventure. Install SimFlow, rediscover the CFD world without any time limit and enjoy powerful fluid simulation software.