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RuiVO October 7, 2011 06:14

How to plot Lift and Drag Coefficients using tecplot 360
Hello, I can calculate the integral values of forces and momentums over an airfoil surface but I can't obtain a plot from it. In the x variable option I can't select x coordinate. Instead the index "i" is selected and I don't see any curves.

Best Regards


giuli@ October 19, 2011 09:09

Hi Rui,
which solver are you using?

RuiVO October 19, 2011 09:13

Hi giuli@, I'm using the simpleFoam solver, for incompressible steady flow over an airfoil.

Best regards


giuli@ October 20, 2011 09:21

I'm not really into OF;
what I remember about plotting Cl in Tecplot360 with Fluent data is that I had to extract the variables I wanted in Fluent itself (saved in .xy files), and than import these and make xy plots in Tecplot.

Try to find the way of telling openfoam to get the Cl, Cd along the desired section for all the X values (what I was doing in Fluent),
Then, make a ".dat" file with this header:


and under, in columns, the corresponding values extracted.

Sorry but it's all I can think now :-/

giuli@ April 13, 2012 06:13

Errata corrige: I was plotting velocities components (it doesn't make sense to plot Cl and Cd along x since these are integral values)

scott_rumage April 13, 2012 14:17


You might review this tip on the Tecplot web site to see if it helps you with your question:


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