calculating loads from VSPAERO

[flashnag]

My goal is to calculate the spanwise lift forces on a wing. From the *.fem  output file, at the bottom, there is a force summation, for example

------------------------------------------

Total Forces and Moments


Total CL:  0.339673
Total CD:  0.003367
Total CS:  -0.000000
Total CFx: -0.033936
Total CFy: -0.000000
Total CFz: 0.337977
Total CMx: -0.000000
Total CMy: -0.127732
Total CMz: -0.000000

----------------------------------------------

What are the units  of "CFz=Component integrated Z force coefficient" ?

To ground my assumptions, my rough estimate for lift is L=S*Cl*q=80m^2*0.35*11.9 N/m^2 = 335 N

if I compute CFz*q*S = 0.338*11.88*80.6 = 327 N, which is quite close to my rough estimate.

How does CFz differ from computing section lift L_i = Cl*s*S_i , where S_i is the section area

from the spanwise, it looks like Cz includes the area?

if I calculate SUM(Cz*q) = 347 N

The only documentation I could find on the output files is here

http://openvsp.org/wiki/doku.php?id=vspaerotutorial

Thanks