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ENH: yPlus: add option to disable wall function contributions (#1773)

Kutalmış Berçin requested to merge enh-aug20.kbc into develop

Summary

See the self-explanatory commit messages.

Resolved bugs (If applicable)

#1773

Details of new models (If applicable)

Small test cases: GL1773-pre-fix.zip vs GL1773-post-fix

Test-case characteristics:

  • One-dimensional smooth-wall plane channel flow, ReTau=5200
  • Number of cells = 20
  • nu = 0.000192827 [m2/s]
  • The case was designed to produce => -1*sqrt(mag(wallShearStress)) = 1
  • The y1+ set (expected) = {0.05, 0.5, 1, 5, 10, 20, 30, 50, 100, 1000}
  • kOmegaSST/SpalartAllmaras, simpleFoam

Main field of interest:

  • mag(wallShearStress) function object returns ~ 1 for all test cases, therefore the expected y1+
  • yPlus function object (min) results for lowerWall rounded up to 2 decimals:

y1+ = 0.05:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 0.12 0.05
nutkWallFunction 0.00025 0.05
nutUSpaldingWallFunction 0.05 0.05
nutUBlendedWallFunction 0.05 0.05
nutLowReWallFunction 0.05 0.05

y1+ = 0.5:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 0.18 0.50
nutkWallFunction 0.025 0.50
nutUSpaldingWallFunction 0.50 0.50
nutUBlendedWallFunction 0.50 0.50

y1+ = 1:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 0.34 1.00
nutkWallFunction 0.1 1.00
nutUSpaldingWallFunction 1.00 1.00
nutUBlendedWallFunction 1.00 1.00

y1+ = 5:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 3.02 5.00
nutkWallFunction 2.75 5.00
nutUSpaldingWallFunction 5.00 5.00
nutUBlendedWallFunction 5.00 5.00

y1+ = 10:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 9.12 10.00
nutkWallFunction 8.31 10.00
nutUSpaldingWallFunction 10.00 10.00
nutUBlendedWallFunction 10.00 10.00

y1+ = 20:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 20.00 20.02
nutkWallFunction 19.30 20.01
nutUSpaldingWallFunction 20.00 20.00
nutUBlendedWallFunction 20.00 20.01

y1+ = 30:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 30.09 30.09
nutkWallFunction 29.91 30.12
nutUSpaldingWallFunction 30.08 30.08
nutUBlendedWallFunction 30.09 30.09

y1+ = 50:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 50.16 50.16
nutkWallFunction 50.51 50.19
nutUSpaldingWallFunction 50.17 50.17
nutUBlendedWallFunction 50.16 50.16

y1+ = 100:

Wall function Pre-fix yPlus Post-fix yPlus (when useWallFunction=false)
nutUWallFunction 100.01 100.01
nutkWallFunction 100.96 100.01
nutUSpaldingWallFunction 100.01 100.01
nutUBlendedWallFunction 100.01 100.01

Risks

  • Compiled with Gcc-7.4.1/Clang-9.0, DPInt32Opt
  • No regression issue: 1-pre-fix-yPlus.zip vs 2-post-fix-yPlus.zip (Test: incompressible/pisoFoam/RAS/cavity)
  • No changes in the default behaviour.
    • User can now select the new behaviour by useWallFunction=false which is by default true.
Edited by Kutalmış Berçin

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