LaminarFlowSolver

This lives in source:Tools/setuptool/InletProcessing

The entry point is source:Tools/setuptool/InletProcessing/Run.py. As in:

python -m InletProcessing.Run path/to/profile.pro

As in the docstring, this script will "Process all the Inlets specified by profileFile, solving the Navier- Stokes equations for steady flow down an infinite channel with the cross section of the inlet. Writes the point ID and the fluid velocity at that point, the velocity being such that the integral of the flow across the channel is unity.

Currently output is written as vtkPolyData to files like
"$GEOMETRYFILEBASENAME.inlet$ID.vtp""

The GeometryInletPointFinder is a "Class to find all the INLET points contained within a geometry file (.gmy). Data is returned as a vtkPolyData, with the 3D index of the points supplied as !CellData in an array named "!PointsIds".

It's based on the hemeTools.parsers.geometry classes."

The SurfaceIntersectionFinder "Contains a VTK pipeline to find the intersection of a Iolet plane with the contents of an STL file, and return this data in SI units.

Pipeline is:

    FileUnitLength ----------------> vtkTransform ------------------------
                                                                          \
    FileName -> vtkSTLReader -> vtkCutter -> vtkPolyDataConnectivityFilter -> vtkTransformPolyDataFilter
                            /            /
    Iolet -----> vtkPlane -            /
            \-------- Centre ---------

The output of the filter is a vtkPolyData describing the closed loop around the tube.

The script iterates over all the inlets in the profile. It creates a Tesselatorwhich is an "Object to transform the iolet sites and edge to the X-Y plane and tesselate the interior with a triangular mesh.

Pipeline is:

    Edge ---------------------------------------------------
          \                                                 \
    Sites--> vtkAppendPolyData -> vtkTransformPolyDataFilter -> vtkDelaunay2D
                              /    
                            /
    Iolet -> vtkTransform-/

This has its inputs (EdgeConnection, SitesConnection, and Inlet) set and the output is sent to the PoiseuilleSolver. The tessellation uses those lattice points that have one or more inlet links, projected into the inlet's plane to form the mesh.

This "Solve[s] the boundary value problem, such that the volume flux (i.e. the integral of the velocity across the inlet surface) is one." It uses the !FiPy finite volume library to solve the NS equations assuming laminar flow, i.e. \partial_t v_i = 0 and v_i \partial_i v_j = 0, which is just a Poisson equation. The answer is normalised to give unit flux.

The solution is interpolated to point data and written to a VTP file.