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<p>Hi,</p>
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<p>I would like to compute a numerical schlieren field from a density field in Paraview. The schlieren variable would just be the magnitude of the density gradient computed at each cell center in the data set. I have been able to compute a basic schlieren
dataset by using the Paraview filter "Gradient of Unstructured DataSet". However I would like to do something like the following.</p>
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<p>1.) Compute density gradients.</p>
<p>2.) Compute the magnitude of the gradients.</p>
<p>3.) Normalize the gradient magnitudes by the maximum value in the domain( so that the new variable goes from 0 to 1 )</p>
<p>4.) Store this new data as a new variable called 'Schlieren'<br>
</p>
<p>5.) Take the new schlieren variable and perform a second point-by-point operation on the data.<br>
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<p> NewSchlieren = exp( -k*oldSchlieren) <br>
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<p>where k is a constant that I set. This 5th operation just serves to sharpen the lines that are present in the oldSchlieren data set.</p>
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<p>I'm thinking that I need to write some sort of programmable filter. I'm just not sure how I would actually perform point-by-point operations on the data sets.<br>
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<p>Any guidance on how to read/operate on variables in the data set would be greatly appreciated.
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<p>Thanks,</p>
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<div style="margin:0"><font face="Calibri,sans-serif" size="2"><span style="font-size:11pt">Christopher R. Neal<span name="searchHitInReadingPane" id="0.6422234599957483" class="highlight"></span></span></font></div>
<div style="margin:0"><font face="Calibri,sans-serif" size="2"><span style="font-size:11pt">Graduate Student
<br>
Center for Compressible Multiphase Turbulence<br>
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<div style="margin:0"><font face="Calibri,sans-serif" size="2"><span style="font-size:11pt">Mechanical and Aerospace Engineering Department<br>
</span></font></div>
<div style="margin:0"><font face="Calibri,sans-serif" size="2"><span style="font-size:11pt">University of Florida</span></font></div>
<div style="margin:0"><font face="Calibri,sans-serif" size="2"><span style="font-size:11pt">Cell: (863)-697-1958</span></font></div>
<div style="margin:0"><font face="Calibri,sans-serif" size="2"><span style="font-size:11pt">E-mail: chrisneal@ufl.edu</span></font></div>
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