(CFD) Determination of the point on which the fluid forces act.

[tom.turcksin]

Hi, I am am working  on a small aircraft.

To determine its stability and and its performance, I am interested in finding the drag and lift force on a body (which think I found in dialog that summarizes the results) but also in finding the point on which these forces act upon  (if friction is ignored this is referred to as the centre of pressure). Basically to have a stabile working conditions, I must ensure the centre  of mass lays upstream of the centre of pressure. From a programming point of view  I know that the total force on a body is simply found by summing the pressure forces for each finite surface of a closed body. To determine the centre of pressure, one should also sum the torque around a certain point (i.e.. the leading edge) for each finite surface and finally the centre of pressure is found by expressing that the torque caused by the total force is equal to the one obtained trough the summation.  

Can anyone help me with this please.???

Many thanks, Tom