Changes between Version 2 and Version 3 of Tutorial/ComparaisonNumSolution


Ignore:
Timestamp:
Feb 19, 2015, 3:13:37 PM (6 years ago)
Author:
vaillant1p
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • Tutorial/ComparaisonNumSolution

    v2 v3  
    1010
    1111== Synthetic Images ==
    12 In the folder 'AnalyticFlows', select one of the images from the 'a3b' series. It shows a diagonal uniform flow running from the bottom left corner to the top right one. '''[RUN]''' a PIV on the images series only using '''[CIV1]''', '''[FIX1]''' and '''[PATCH1]''' with the default parameters.
     12In the folder '!AnalyticFlows', select one of the images from the 'a3b' series. It shows a diagonal uniform flow running from the bottom left corner to the top right one. '''[RUN]''' a PIV on the images series only using '''[CIV1]''', '''[FIX1]''' and '''[PATCH1]''' with the default parameters.
    1313Then '''[Open]''' one of the vector files (.civ) created. We need to substract the numerical solution to this image in order to keep only the errors between our calculation and the theorical one. Select the mall red square'''[SubField]''' under the '''[Input]''' table to open a second file in '''uvmat'''. Open the netcdf file of the synthetic solution 'a3b_sol_num.nc'. The GUI '''get_field''' pops up, select 'vectors' in the '''[!FieldOptions]''' table and 'U' and 'V' in the right and left tables under '''[Ordinate]'''. The '''[Coordinates]''' should still remain as 'X' and 'Y'. Click on '''[OK]'''. An 'ERROR' window pops up, select '''[OK]''' and close the GUI '''set_object]''' which automatically popped up.
    1414
     
    2323Once it is done, the GUI '''get_field''' pops up again. Keep '1D plot' in the '''[!FieldOptions]''' table and select 'UHisto' or 'Vhisto' in the '''[Ordinate]''' one. The '''[Coordinates]''' should change according to the input in the '''[Ordinate]''' ('U' if 'UHisto' is selected, same for 'V' and 'VHisto'). Select '''[OK]'''.
    2424
    25 A curve, close to a Gaussian, (gathering all the vectors from the difference between all the analytic and synthetic files of the series) appears in '''uvmat'''. On the right hand corner a table shows all the parameters of this curve. In the scroll bar '''[Field/get_field]''' it is possible to get back to the GUI '''get_field''' and change the '''[Ordinate]'''. You can also '''[Export]''' the curve '''[/in new figure]''' or '''[/on existing axis]'''.
     25A curve, close to a Gaussian, (gathering all the vectors from the difference between all the analytic and synthetic files of the series) appears in '''uvmat'''. On the right hand corner a table shows all the parameters of this curve. In the scroll bar '''[Field/get_field]''' it is possible to get back to the GUI '''get_field''' and change the '''[Ordinate]'''. You can also '''[Export]''' the curve '''[in new figure]''' or '''[on existing axis]'''.
    2626
    2727This is useful to determine and optimize some PIV parameters. The figure below shows the RMS, !FirstCentile, !FirstDecile, !LastDecile and !LastCentile of PIV calculations with different '''[CorrBoxSize]'''.
     
    3838
    3939
    40 It is now possible to '''[Run]''' a '''[/PIV]''' on this serie and by following all the steps from part1 (Synthetic Images) to obtain the difference between the analytical and noise solution and the synthetic one. The curve is not as smooth as in part1, you can indeed notice the effect of noise in a PIV calculation.
     40It is now possible to '''[Run]''' a '''[PIV]''' on this serie and by following all the steps from part1 (Synthetic Images) to obtain the difference between the analytical and noise solution and the synthetic one. The curve is not as smooth as in part1, you can indeed notice the effect of noise in a PIV calculation.
    4141
    4242