Forces and moments
I am analyzing a body of revolution, 1.1 m long and 0.16 m diameter. I use the freestream boundary condition.
functionObjectLibs ( "libforces.so" );
patches ( body ); // the <body> is a group of patches
rhoName rhoInf; // Indicates incompressible
rhoInf 1.225; // Redundant for incompressible
liftDir (0 0 1);
dragDir (1 0 0);
CofR (0 0 0); // Axle midpoint on ground
pitchAxis (0 1 0);
lRef 3; // Wing root cord
Aref 0.0707; // Estimated
However, I get very strange lift and drag results a an alfa of 0, 5 and 10 degrees. The drag values are reasonable, but the lift is very small.
I use the body-referenced coordinate system for lift and drag directions.
Are the lift and drag force supposed to be summed for all the pathches in the group <body>? The thing is, they do not. I have summed for all the patches manually and then the results matches wind tunnel results pretty good (for CFD results).
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