The OpenFOAM User Guide provides an introduction to OpenFOAM, through some basic tutorials, and some details about the general operation of OpenFOAM. OpenFOAM is a collection of approximately 250 applications built upon a collection of over 100 software libraries (modules). Each application performs a specific task, e.g the snappyHexMesh application can generate meshes for complex geometry, such as a vehicle. The simpleFoam application could then be used to simulate steady-state, turbulent, incompressible flow around the vehicle…
OpenFOAM Documentation
CFD Direct provide the following Free OpenFOAM Documentation for the users of OpenFOAM. We will periodically add new documents to this resource. The OpenFOAM User Guide is a web-friendly, online version of the latest User Guide provided with OpenFOAM. Please report any corrections to the OpenFOAM Issue Tracking system, where we will endeavour to make corrections as soon as possible.
C++ Source Guides: click here
Energy Equation in OpenFOAM

This article provides information on the equation describing conservation of energy relevant to fluid dynamics and computational fluid dynamics (CFD). It first assembles an equation for combined mechanical and thermal energy, i.e. total energy, in terms of material derivatives. It then presents an equation for thermal, or internal, energy. The total energy equation is then provided in terms of local (partial) derivatives, both in terms of internal energy and enthalpy. The implementation of the energy equation in solvers in OpenFOAM is then described.
Tensor Mathematics

This article provides information on tensor mathematics, relevant to fluid dynamics and computational fluid dynamics (CFD). It describes scalars and vectors and typical algebraic vector operations. It follows with second rank tensors, their algebraic operations, symmetry, skewness and tensor invariants such as trace and determinant, higher rank tensors, co-ordinate system and change of axis. Tensor calculus is introduced (div, grad, curl and Laplacian), followed by integral theorems of Gauss and Stokes, with a physical representation of div and curl, and more.
Computational Fluid Dynamics

Fluid dynamics is concerned with the motion of fluids (liquids and gases) and the forces on them. “Computational” refers to computation of the flow and forces using numerical analysis. We define “computational fluid dynamics” as “the prediction of fluid motion and forces by computation using numerical analysis, generally extended to include heat, thermodynamics, chemistry and solids”. This definition covers a broad range of calculations for numerous scientific and engineering applications, in particular involving heat.
OpenFOAM Linux Guide

This guide provides information and example terminal commands for Linux, relevant to users of OpenFOAM. Commands are written that refer to OpenFOAM, e.g. they include OpenFOAM Linux environment variables. Those commands that refer to OpenFOAM will only function as stated, if they are executed on a machine on which OpenFOAM is installed and the user’s environment variables are set up for OpenFOAM, e.g. as described in the source download page (see Setting Environment Variables).
OpenFOAM v4 User Guide

The OpenFOAM v4 User Guide provides an introduction to OpenFOAM, through some basic tutorials, and some details about the general operation of OpenFOAM. OpenFOAM is a collection of approximately 250 applications built upon a collection of over 100 software libraries (modules). Each application performs a specific task, e.g the snappyHexMesh application can generate meshes for complex geometry, such as a vehicle. The simpleFoam application could then be used to simulate steady-state, turbulent, incompressible flow around the vehicle…
OpenFOAM v3 User Guide

The OpenFOAM v3 User Guide provides an introduction to OpenFOAM, through some basic tutorials, and some details about the general operation of OpenFOAM. OpenFOAM is a collection of approximately 250 applications built upon a collection of over 100 software libraries (modules). Each application performs a specific task, e.g the snappyHexMesh application can generate meshes for complex geometry, such as a vehicle. The simpleFoam application could then be used to simulate steady-state, turbulent, incompressible flow around the vehicle…
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