KNOWN ISSUE: Fourier peak statistics are not working for charts in CFD-Post

If a transient chart is set up to use a Fast Fourier Transform, then selecting the Statistics for a chart line or series should give list of the largest Fourier peaks. However, these are missing.

A coding error means that CFD-Post does not display the peaks.

CFD-Post is still calculating the positions of the Fourier peaks even though it is not displaying them. The values can be extracted using the Command Editor using Power Syntax. The following example shows how to extract the Fourier peaks for the chart line Chart Line 1, which is part of Series 1, from Chart 1. If the following is pasted into the Command Editor, and processed, it writes the values to a table in the file "peaks.txt" in the working directory of CFD-Post. This can easily be adapted to suit individual cases.

! open(FILE,">>peaks.txt") or &abort_unt("Error opening file");
! my $vals = getValue("/CHART:Chart 1/CHART SERIES:Series 1/CHART LINE:Chart Line 1", "FFT Peaks");
! my @peaks=split(/,/,"$vals");
! my $arraysize=@peaks;
! for($counter = 0; $counter < $arraysize/2; $counter++){
! print FILE "$peaks[2*$counter+1]t$peaks[2*$counter]n";
! }

Alternatively, it is possible to export the data from the Fourier chart and locate the peaks manually.

ANSYS CFX Release 12.1.

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