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BluntStreamlines

vtk-examples/Python/VisualizationAlgorithms/BluntStreamlines

Description

This example shows airflow around a blunt fin. This example consists of a wall with half a rounded fin projecting into the fluid flow. (Using arguments of symmetry, only half of the domain was modeled.) Twenty-five streamlines are released upstream of the fin. The boundary layer effects near the junction of the fin and wall are clearly evident from the streamlines. In this area, flow recirculation is apparent, as well as the reduced flow speed.

Info

See Figure 6-19 in Chapter 6 the VTK Textbook.

Other languages

See (Cxx)

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

BluntStreamlines.py

#!/usr/bin/env python

# noinspection PyUnresolvedReferences
import vtkmodules.vtkInteractionStyle
# noinspection PyUnresolvedReferences
import vtkmodules.vtkRenderingOpenGL2
from vtkmodules.vtkCommonColor import vtkNamedColors
from vtkmodules.vtkFiltersCore import vtkStructuredGridOutlineFilter
from vtkmodules.vtkFiltersFlowPaths import vtkStreamTracer
from vtkmodules.vtkFiltersGeometry import vtkStructuredGridGeometryFilter
from vtkmodules.vtkFiltersSources import vtkLineSource
from vtkmodules.vtkIOParallel import vtkMultiBlockPLOT3DReader
from vtkmodules.vtkRenderingCore import (
    vtkActor,
    vtkPolyDataMapper,
    vtkRenderWindow,
    vtkRenderWindowInteractor,
    vtkRenderer
)


def main():
    xyzFilename, qFilename = get_program_parameters()

    colors = vtkNamedColors()

    aren = vtkRenderer()
    renWin = vtkRenderWindow()
    renWin.AddRenderer(aren)
    iren = vtkRenderWindowInteractor()
    iren.SetRenderWindow(renWin)

    scalarRange = [0.0] * 2
    c = [0.0] * 3
    maxTime = 0.0

    reader = vtkMultiBlockPLOT3DReader()
    reader.SetXYZFileName(xyzFilename)
    reader.SetQFileName(qFilename)
    reader.Update()  # Force a read to occur.

    pd = reader.GetOutput().GetBlock(0)
    pd.GetCenter(c)
    if pd.GetPointData().GetScalars():
        pd.GetPointData().GetScalars().GetRange(scalarRange)
    if pd.GetPointData().GetVectors():
        maxVelocity = pd.GetPointData().GetVectors().GetMaxNorm()
        maxTime = 20.0 * pd.GetLength() / maxVelocity

    outlineF = vtkStructuredGridOutlineFilter()
    outlineF.SetInputData(pd)

    outlineMapper = vtkPolyDataMapper()
    outlineMapper.SetInputConnection(outlineF.GetOutputPort())

    outline = vtkActor()
    outline.SetMapper(outlineMapper)
    outline.GetProperty().SetColor(colors.GetColor3d('Moccasin'))
    outline.GetProperty().SetLineWidth(2.0)

    #
    # Some geometry for context
    #
    wall = vtkStructuredGridGeometryFilter()
    wall.SetInputData(pd)
    wall.SetExtent(0, 100, 0, 100, 0, 0)

    wallMap = vtkPolyDataMapper()
    wallMap.SetInputConnection(wall.GetOutputPort())
    wallMap.ScalarVisibilityOff()

    wallActor = vtkActor()
    wallActor.SetMapper(wallMap)
    wallActor.GetProperty().SetColor(colors.GetColor3d('Silver'))

    fin = vtkStructuredGridGeometryFilter()
    fin.SetInputData(pd)
    fin.SetExtent(0, 100, 0, 0, 0, 100)

    finMap = vtkPolyDataMapper()
    finMap.SetInputConnection(fin.GetOutputPort())
    finMap.ScalarVisibilityOff()

    finActor = vtkActor()
    finActor.SetMapper(finMap)
    finActor.GetProperty().SetColor(colors.GetColor3d('Silver'))
    #
    # regular streamlines
    #
    line1 = vtkLineSource()
    line1.SetResolution(25)
    line1.SetPoint1(-6.36, 0.25, 0.06)
    line1.SetPoint2(-6.36, 0.25, 5.37)

    rakeMapper = vtkPolyDataMapper()
    rakeMapper.SetInputConnection(line1.GetOutputPort())

    rake1 = vtkActor()
    rake1.SetMapper(rakeMapper)
    rake1.GetProperty().SetColor(colors.GetColor3d('Black'))
    rake1.GetProperty().SetLineWidth(5)

    streamers = vtkStreamTracer()
    # streamers.DebugOn()
    streamers.SetInputConnection(reader.GetOutputPort())
    streamers.SetSourceConnection(line1.GetOutputPort())
    streamers.SetMaximumPropagation(maxTime)
    streamers.SetInitialIntegrationStep(0.2)
    streamers.SetMinimumIntegrationStep(0.01)
    streamers.SetIntegratorType(2)
    streamers.Update()

    streamersMapper = vtkPolyDataMapper()
    streamersMapper.SetInputConnection(streamers.GetOutputPort())
    streamersMapper.SetScalarRange(scalarRange)

    lines = vtkActor()
    lines.SetMapper(streamersMapper)

    aren.AddActor(outline)
    aren.AddActor(wallActor)
    aren.AddActor(finActor)
    aren.AddActor(rake1)
    aren.AddActor(lines)
    aren.SetBackground(colors.GetColor3d('Gray'))

    aren.ResetCamera()
    aren.GetActiveCamera().Elevation(30.0)
    aren.GetActiveCamera().Azimuth(30.0)
    aren.GetActiveCamera().Dolly(1.2)
    aren.ResetCameraClippingRange()

    renWin.SetSize(640, 480)
    renWin.SetWindowName('BluntStreamlines')
    renWin.Render()

    # Interact with the data.
    iren.Start()


def get_program_parameters():
    import argparse
    description = 'This example shows airflow around a blunt fin.'
    epilogue = '''
    '''
    parser = argparse.ArgumentParser(description=description, epilog=epilogue,
                                     formatter_class=argparse.RawDescriptionHelpFormatter)
    parser.add_argument('filename1', help='bluntfinxyz.bin.')
    parser.add_argument('filename2', help='bluntfinq.bin.')
    args = parser.parse_args()
    return args.filename1, args.filename2


if __name__ == '__main__':
    main()