# FEM: Risolutore Elmer

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Nome nel codice |
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FEM SolverElmer |

Posizione nel menu |

Solve → Risolutore Elmer |

Ambiente |

FEM |

Avvio veloce |

Introdotto nella versione |

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Vedere anche |

Tutorial FEM |

## Description

Elmer is an open source multiphysical simulation software mainly developed by CSC - IT Center for Science (CSC). Elmer development was started 1995 in collaboration with Finnish Universities, research institutes and industry. After it's open source publication in 2005, the use and development of Elmer has become international.

Elmer includes physical models of fluid dynamics, structural mechanics, electromagnetics, heat transfer and acoustics, for example. These are described by partial differential equations which Elmer solves by the Finite Element Method (FEM). https://www.csc.fi/web/elmer

Creating the ElmerSolver object in the Analysis container in FreeCAD, gives access to the Elmer Equations for simple or multiphysical analysis.

Da fare

## Installation

Elmer requires two components to be interfaced with FreeCAD, ElmerGrid is the interface handling meshes and ElmerSolver is handling the computation. There are standalone programs for both of these applications but their installation and usage are beyond the scope of the FreeCAD integration.

- Go to the CSC binaries resources for Elmer: https://www.nic.funet.fi/pub/sci/physics/elmer/bin/ OR https://www.csc.fi/web/elmer/binaries
- Download and install the version best suited to your Operating System (Windows 64 bits or Linux)
- In FreeCAD go to
**Edit**-->**Preferences**-->**FEM**-->**Elmer** - Link the correct path for both ElmerGrid.exe and ElmerSolver.exe

You are ready to use Elmer in FreeCAD.

## Usage

- In FreeCAD go to FEM workbench
- Create an Analysis container
- Create a FEM Solver for Elmer A successful analysis will require at least a Model (2D or 3D), a Material (Fluid or Solid, a Mesh, Equations and Boundary conditions
- Edit the parameters for the solver in the Data tab of the ElmerSolver object in the model tree
- Double-click on the ElmerSolver object to prepare an analysis run
- Select the path to write the analysis in
- Click
**Write**to write the case files in the directory selected previously - Click
**Run**to start the analysis

**About Equations:**

- Each type of analysis in Elmer is called an Equation (Flow, Heat, Electrostatics...)
- One or several equations can be used at once with Elmer by simply adding the Equation object under the ElmerSolver object:

- Click on the ElmerSolver object
- Select an equation:

## Notes

- Parameters for the Solver and for the Equations are independently set through the Data tab of their respective objects in the tree.
- Each equation will have a priority, for example, if trying see the effect of a convective flow of hot air, the equation for Flow should be solved with higher priority than Heat, otherwise the solver will first solve Heat through conduction and then Flow.

## Documentation

The following link gives access to the full documentation for Elmer https://www.nic.funet.fi/pub/sci/physics/elmer/doc/ This includes the manuals as well as tutorials. Note that documentation and files appended with "gui" generally concern the usage of the Elmer GUI and not the FreeCAD implementation of Elmer.

**Materials:**Solid, Fluid, Nonlinear mechanical; Material editor

**Element geometry:**Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)

**Constraints**

**Electrostatic:**Potential

**Fluid:**Initial velocity, Fluid boundary, Flow velocity

**Mechanical:**Fixed, Displacement, Plane rotation, Contact, Transform, Force, Pressure, Self weight, Bearing, Gear, Pulley

**Thermal:**Initial temperature, Heat flux, Temperature, Heat source

**Solve:**Calculix tools, CalculiX, Elmer, Z88;**Equations:**Heat, Elasticity, Electrostatic, Fluxsolver, Flow;**Solver:**Solver control, Solver run

**Results:**Purge, Show;**Postprocessing:**Apply changes, Pipeline from result, Create warp vector filter, Create scalar clip filter, Create cut filter, Create clip filter, Create data along line filter, Create linearized stresses,

Create data at point filter, Create functions

**Utilities:**Clipping plane, Remove clipping planes; Mesh clear, Mesh print info

**Additional:**Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Project, FEM Concrete; FEM Element Types

**Installazione:**Unix, Windows, Mac;**Getting started****Base:**About FreeCAD, Workbenches, Preferences, Document structure, Interface Customization, Properties, Mouse Model; Tutorials**Ambienti**: Menu di base; Arch, Draft, FEM, Image, Inspection, Mesh, OpenSCAD, Part, PartDesign, Path, Plot, Points, Raytracing, Reverse Engineering, Robot, Ship, Sketcher, Spreadsheet, Start, Surface workbench, TechDraw, Test Framework, Web

**Scripting:**Introduction to Python, FreeCAD scripting tutorial, FreeCAD Scripting Basics, How to install macros, Gui Command, Units**Modules:**Builtin modules, Workbench creation, Installing more workbenches**Meshes:**Mesh Scripting, Mesh Module**Parts:**The Part Module, Topological data scripting, PythonOCC, Mesh to Part**Coin scenegraph:**The Coin/Inventor scenegraph, Pivy**Qt interface:**PySide, Using the FreeCAD GUI, Dialog creation**Parametric objects:**Scripted objects**Other:**Code snippets, Line drawing function, Embedding FreeCAD, FreeCAD vector math library, Power users hub, Python, Macros, FreeCAD Scripting Basics, Topological data scripting