CFD Exercises 1 Course : Aer E 311L Gas Dynamics Lab

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CFD Exercises 1Course Aer E 311L Gas Dynamics
Lab
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FLOWLAB - USAGE

• Flowlab is installed in the windows labs. Go to
  Start -gt All Programs . Run Flowlab1.1.
• This creates a file called Flowlab.ini in
  C\Documents and Settings\user. It looks as
  follows
• FLOWLAB_WORK_DIR C\Temp\myflowlab
• FLOWLAB_TEMPLATE_DIR z\Flowlab1.1\templates\nozz
  le
• All your work is saved in FLOWLAB_WORK_DIR.
• Remember to copy your final files to your home
  area in Clue or AFS.
• Add AFS directory in the following way.
• Start the AFS client.
• Add \afs\iastate.edu\general\aero311l\Flowlab1.1\t
  emplates as F\
• Define FLOWLAB_TEMPLATE_DIR to F\

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FLOWLAB - GEOMETRY

• Create a nozzle without plenum with the following
  dimensions
• L1 .1016
• L2 .0368
• R1 .0128
• R2 .0101
• R3 .0114

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FLOWLAB - PHYSICS

• For the nozzle without plenum generated in
  previous exercise, set the boundary conditions in
  Flowlab by the following specifications. Choose
  inviscid model.
• Inlet
• Total pressure - 130000 Pa
• Total temperature - 300 K
• Outlet and plenum
• Pressure (static) 101325 Pa
• Temperature (static) 300 K

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FLOWLAB - MESH

• Continuing from the previous problem, create mesh
  using automatic-gtmedium option. The mesh should
  look like the following.

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FLOWLAB SOLVE/REPORTS

• Using the results for previous problems, and the
  default settings for converge criteria ( note the
  value ), solve.
• Generate mach number plot at centerline.

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FLOWLAB POST PROCESSING

• Generate contour plots for density, pressure and
  mach number for the nozzle.

Contour plot for mach number.
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FLOWLAB SUGGESTIONS

• The display for the residual (XY plot) does not
  refresh properly if a new run is submitted after
  a previous run in the same section.
• Workaround Start a new session.
• Try to save your work as often as possible.
• Most of the defaults are set to the nozzle
  dimension in the experiment. Use them.
• If the pressure ratio is low, and the
  computational domain is large, there are
  convergence problems. So when having convergence
  problems, go for a small domain.