Creating a new example

How to Create an Example in PorousLab

The PorousLab framework is designed for object-oriented simulation of porous media problems. A simulation follows a well-defined workflow involving two main objects:

• mdl: the model object (geometry, materials, boundary conditions)
• anl: the analysis object (solver settings, execution)

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General Workflow

Algorithm: Setting up an example in PorousLab

1. Create and configure the model object (mdl):
   a. Instantiate the appropriate model class 
      (e.g., Model_H, Model_M, Model_HM)
   b. Load or generate mesh data: node, elem
   c. Set the mesh using: mdl.setMesh(node, elem)
   d. Define and configure material objects 
      (e.g., PorousMedia, Fluid)
   e. Assign materials to the model: mdl.setMaterial(...)
   f. Apply boundary and initial conditions

2. Create and configure the analysis object (anl):
   a. Instantiate analysis class 
      (e.g., Anl_Linear, Anl_Transient)
   b. Set solver parameters (e.g., time step, tolerances)

3. Run the simulation:
   anl.run(mdl)

4. Post-process the results:
   Use built-in tools such as:
   - mdl.plotField('variable')
   - mdl.plotFieldAlongSegment(...)
   - mdl.plotDeformedMesh(...)

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Pre-processing

Mesh Generation

PorousLab uses:

• NODE: an [nNodes x 2] matrix with node coordinates
• ELEM: a {nElem x 1} cell array with element connectivity

Meshes can be:

• Generated internally with regularMesh(...)
• Imported from external tools such as Gmsh using this converter

Assign mesh to the model with:

mdl.setMesh(node, elem);

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Boundary Conditions

You can apply Dirichlet and Neumann BCs in three ways:

• At node: setDirichletBCAtNode, setNeumannBCAtNode
• At point: setDirichletBCAtPoint, setNeumannBCAtPoint
• At border: setDirichletBCAtBorder('left'), etc.

Physics-specific methods like:

• setPressureDirichletBCAtNode
• setDisplacementDirichletBCAtBorder

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Post-processing

Visualization is done through FEMPlot methods:

• plotField('pressure'): scalar field contour
• plotFieldAlongSegment(p1, p2, 'pressure'): profile plot
• plotDeformedMesh(scale): view deformed configuration (mechanics)

Textual outputs:

• printResults(): print nodal results
• printResultsHeader(): customize variable labels

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