Tutorial To Set Up A Case For Chtmultiregionfoam In Openfoam 2.0.0

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  Tutorial to set up a case forchtMultiRegionFoam in OpenFOAM2.0.0 Arpit SinghalUniversity of LuxembourgMarch 3, 2014 The OpenFOAM-solver chtMultiRegionFoam is meant to be used for heat-transfer between a solid and a fluid srcinally. As it does work with differentregions of different properties, the setup is therefore different from the otherOpenFOAM cases.This tutorial is written for setting up a basic case for chtMultiRegionFoam(cMRF) in an Openfoam.tutorial  Contents 1 Contents 1 Introduction 22 Basic Workflow 33 chtMRF Case Setup 4 3.1 Geometry and Mesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43.2 Creating the Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53.2.1 Declaring the Regions . . . . . . . . . . . . . . . . . . . . . . . . 53.2.2 Defining the Region by Zones . . . . . . . . . . . . . . . . . . . . 63.3 Splitting the Mesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73.4 Necessary Files and Folders . . . . . . . . . . . . . . . . . . . . . . . . . 83.4.1 Files setup by the user . . . . . . . . . . . . . . . . . . . . . . . . 93.4.2 Files setup by OpenFOAM utilities . . . . . . . . . . . . . . . . . 15 4 Running the case 185 Using scripting 186 Appendice 21 tutorial  1 Introduction 2 1 Introduction What is meant by ”multiregion multi physics modeling”? It is inherently-coupled physicson disparate continua (e.g. fluid, solid, different solids). In multiregion multi physicsseparate governing equations for each continuum/region are solved, as shown in 1.1seperate governing equations will be solved for Region 1 and Region 2 depending upontheir phase and Γ represents a region interface. A region can be defined as coherentcontinum of the same phase.Figure 1.1: ExampleGenerally two different approaches to solving such problems are distinguished: ã  Monolithic: use same primitive variables, cast governing equations in terms of these variables, solve a single coupled matrix equation system ã  Partitioned: separate governing equations, solve separate matrix equation systems,couple at the boundary interface, sub-iterate until coupled convergence is reachedHere, we focus on partitioned approaches using OpenFOAM’s multiregion function-ality (conjugate heat/mass transfer). For a multiregion partitioned solver the workingsteps are as follows:1. Define multiple meshes, one for each ”region”2. Create field variables on each mesh3. Solve separate governing equations on each mesh4. Multiregion coupling at the boundary interface between regions5. Subiterate until fully-coupled solution is reachedtutorial  2 Basic Workflow 3 2 Basic Workflow The basic work flow for a case setup is explained in fig. 2.1.Figure 2.1: The case visualization in 2Dtutorial