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FLUENT report forces in term of pressure force and viscous force. For instance, we are interested in the drag on the airfoil,

(Drag)_total = (Drag)_pressure + (Drag)_viscous

Drag due to pressure:

{latex}
\large
$$
{(Drag)_{pressure}} = {\oint \-P \hat{n}.\hat{e_d}dS}
$$
{latex}

Drag due to viscous effect:

{latex}
\large
$$
{(Drag)_{viscous}} = {\oint \tau_w \hat{t}.\hat{e_d}dS}
$$
{latex}

where

e_d is the unit vector parallel to the flow direction. 

n is unit vector perpendicular to the surface of airfoil.

t is unit vector parallel to the surface of airfoil.

Similarly, if  we are interested in the lift on the airfoil,

(Lift) = (Lift)_pressure + (Lift)_viscous

Lift due to pressure:

{latex}
\large
$$
{(Lift)_{pressure}} = {\oint \-P \hat{n}.\hat{e_l}dS}
$$
{latex}

Lift due to viscous effect:

{latex}
\large
$$
{(Lift)_{viscous}} = {\oint \tau_w \hat{t}.\hat{e_l}dS}
$$
{latex}

where

e_l is the unit vector perpendicular to the flow direction. 

n is unit vector perpendicular to the surface of airfoil.

t is unit vector parallel to the surface of airfoil.