Surface Restricted Traces and Line Integral Convolution

Utilze EnSight to investigate two types of surface streamlines: Surface Restricted Traces (using Particle Trace) and LIC (Line Integral Convolution)

Intended to work with EnSight version 24.2 or later

Start an EnSight session

Launch and connect to an instance of EnSight. This example uses a local EnSight installation.

from ansys.pyensight.core import LocalLauncher

session = LocalLauncher().start()

# Setup shortcuts for long winded calls.
eocore = session.ensight.objs.core
eoutil = session.ensight.utils

Load a dataset

Load Shuttle Session file included in the EnSight installation and render

session.ensight.objs.ensxml_restore_file(
    f"{session.cei_home}/ensight{session.cei_suffix}gui/demos/Shuttle Basic.ens"
)
session.ensight.view.highlight_parts("OFF")
session.ensight.view_transf.fit(0)
session.show("image", width=800, height=600)

Option 1. Using Particle Trace to create Surface Restricted Traces

Using a Particle Trace capability Parent Part and Emit part are the same part. Surface Restriction is ON. .. image:: /_static/05_srt_lic_1.png

emitter_part = eoutil.parts.select_parts_by_dimension(2)
parent_parts = emitter_part
npts = 1500  # number of emitters
vector_var = eocore.VARIABLES["Momentum"][0]  # Vector variable to use

SRTpart = eoutil.parts.create_particle_trace_from_parts(
    "SurfaceRestrictedTrace",
    vector_var,
    parts=emitter_part,
    source_parts=parent_parts,
    direction="+/-",
    surface_restrict=True,
    num_points=npts,
)
session.show("image", width=800, height=600)

Change Visual Attributes

Modify the attributes of the Surface Restricted Traces to be visually closer to Flourescene or Titantiam Dioxide (experimental use)

SRTpart.colorbyrgb = [0, 1, 0]
SRTpart.OPAQUENESS = 0.25
session.show("image", width=800, height=600)

Try Line Integral Convolution (LIC) instead

As we don’t already have a near-surface, non-zero vector defined we need to create ‘Offset’ Variable. Create Offset Variable for Value of Momentum at 2.e-5 distance into fluid domain Specify Offset Variable as the variable for LIC. Specify High Contrast and 1 length for the LIC Specify that we want to see LIC for the Shuttle Surface

SRTpart.VISIBLE = False
session.ensight.part.select_byname_begin("(CASE:Case 1)Shuttle")
session.ensight.variables.evaluate("OffsetVar = OffsetVar(plist,Momentum,2e-05)")

session.ensight.case.sft_variable("OffsetVar")
session.ensight.case.sft_contrast("ON")
session.ensight.case.sft_norm_length(1.000000)

session.ensight.part.select_byname_begin("(CASE:Case 1)Shuttle")
session.ensight.part.show_sft("ON")
session.show("image", width=800, height=600)

Thumbnail sphinx_gallery_thumbnail_path = ‘_static/05_srt_lic_3.png’

session.close()