openfoam/etc/templates/inflowOutflowRotating/README

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Overview
========
+ Template case for rotating geometry flow with single inlet and outlet
+ Can be used for MRF or AMI simulations
+ Setup to run the simpleFoam solver for MRF, pimpleFoam for AMI
+ The case is designed to be meshed with snappyHexMesh
+ snappyHexMesh is setup to use 3 trisurface files
+ fixed.obj: CAD of the stationary geometry
+ rotating.obj: CAD of the rotating geometry
+ rotatingZone.obj: CAD of surface bounding the rotating region
+ Copy the *.obj files to the constant/triSurface directory
+ The fixed.obj should contain an inlet and outlet region to create the relevant
patches in the mesh
Background Mesh
===============
+ The blockMeshDict file contains a configuration for a cylindrical background
mesh aligned along the z-axis
+ The mesh includes a core box-shaped block and inner and outer cylinders
+ The backgroundMesh subdictionary includes key geometric parameters of the mesh
+ The inner cylinder relates to the rotatingZone.obj
+ The outer cyliner relates to the external boundary, e.g. fixed.obj
+ Set the radii of inner and outer cylinders to ~2% larger than respective OBJ
files
+ The background mesh can define the external boundary by uncommenting
entries, e.g. inlet, in the boundary section of blockMeshDict
+ Set background mesh density with boxCells, inCells, outCells and zCells
+ Run blockMesh
+ NOTE: An alternative blockMeshDict-box file exists if the user wants a regular
box-shaped background mesh, similar to set up in the inflowOutflow template
Features
========
+ Run surfaceFeatureExtract to extract features for explicit feature capturing
Castellated Mesh
================
+ In the snappyHexMeshDict file, replace <inletPatch> with the name of the inlet
region in the fixed.obj file, if it defines the external boundary
+ Replace <outletPatch> with the name of the outlet region
+ run snappyHexMesh to obtain a castellatedMesh
+ Review the mesh; modify refinement levels and regenerate the mesh as required
(levels are set in refinementSurfaces and refinementRegions)
Snapped Mesh
============
+ In snappyHexMeshDict, set castellatedMesh off; snap on;
+ Run the snapping phase of snappyHexMesh
+ Review the mesh
Layers
======
+ To add layers to the mesh along wall boundary patches...
+ Switch on addLayers; switch snap off;
+ Run snappyHexMesh
+ The number of layers can be changed by modifying nSurfaceLayers
Initialisation
==============
+ In the field files in the 0 directory, set inlet values
+ For example, in 0/U, set the inlet velocity Uinlet
+ Set the viscosity in constant/transportProperties
+ Rotating properties are set in constant/rotatingZoneProperties
+ For MRF, this file is included from system/fvOptions
+ For AMI, this file is included from constant/dynamicMeshDict
+ Ensure settings are appropriate in controlDict, fvSchemes, fvSolution, for
relevant simulation; for AMI, in particular, ensure that deltaT, ddtSchemes
and relaxationFactors are set for transient simulation