# Day 6

Welcome to Day 6. By now you should have a good understanding of the very basics of OpenFOAM. Today we will further improve your knowledge by going in the direction of real-world applications. You cannot mesh everything with the simple blockMesh utility. For real life geometries you will need more. Today you will learn this by creating your own

• geometry
• mesh

Go back to "3 weeks" series.

## Open source geometry creation

Here you will get a detailed introduction into two alternatives for the creation of geometries as inputs for a CFD project in OpenFOAM

• Salome
• Onshape

## Meshing with blockMesh

The blockMesh is a very simple and powerful tool or utility of OpenFOAM to create simple 1D/2D/3D geometries and mesh it. In this tutorial series a detailed overview is given using a lid driven cavity case.

All major sections of blockMeshDict are discussed with different hands on modifications. In addition an explanation of the sub-section edges & mergePatchPair of blockMeshDict is explained in these tutorials. How one can create an arc and polyline using edges section and merge two blocks using mergePatchPair section is discussed with hands on modifications. Additionally, this tutorial describes how one can create finer mesh near a particular face in blockMeshDict, simpleGrading is used.

## Meshing with snappyHexMesh

The saying goes "Who owns the mesh, owns the solution". In OpenFOAM there are several ways to set up a mesh. On the one hand you can import it from external tools, you can use the simple blockMesh utility [1] [2] [3] or you can create your arbitrary mesh with snappyHexMesh. This tutorial will show you all the possibilities. The topics covered are:

• mesh quality assessment
• mesh conversion from external tools
• blockMesh
• snappyHexMesh

## Meshing with cfMesh

An alternatives for snappyHexMesh is cfMesh. In this tutorial you will get a compact introduction into the work flow of the basics. The following topics are covered:

• geometry definition
• basic mesh refinement
• local refinement along STL files

## How To Build a complete OpenFOAM Project - Exhaust manifold

In this tutorial you will learn how you can start your own simulation project. There is a heavy focus on meshing in Videos 1-10. You will learn about:

• starting a project
• preparing the geometry
• repairing the geometry
• surface triangulation
• STL preparation
• first meshing
• mesh optimization

# End of Day 6

Today you made a big step towards the real life application of CFD in OpenFOAM by learning and understanding how to create a mesh in OpenFOAM. Tomorrow we will continue with simulations including turbulence modeling. If you've finished the day with time to spare, why not try the additional examples below!

See you tomorrow!

### snappyHexMesh – Single region

Mesh a flange geometry and simulate heat transfer in it using scalarTransportFoam.

• The aim of the tutorial is to give a basic introduction to single region meshing with the meshing tool snappyHexMesh
• Understanding the advantages of snappyHexMesh
• Understanding the three basic steps of snappyHexMesh

### snappyHexMesh – Multi region

In this tutorial a geometry with more than one region is meshed using snappyHexMesh and simulated using chtMultiRegionFoam.

• Understanding multi region meshing with the meshing tool snappyHexMesh
• Multi region simulations