Downforce

[OCCxlr8ed]

Ok need some help here with downforce:

So far what i understand is that due to the different areas which air have to cover, when it goes over a surface with a larger area at the same time where the otherside has a smaller area the top will have a greater velocity and due to Bernoullis Principle it will have a decrease in pressure.

Vice-versa for the bottom side.

What i don't understand is how the force is applied?

From Wikipedia.org i found this image here:

http://upload.wikimedia.org/math/6/5/b/65b94fadeb8c96552b6242d37ed84efb.png

Which is the equation for determining Lift. Would downforce just be negative lift? Another two things which i dont understand in that equation is the "frontier of the domain? and the last three terms.

Is there a simple way of explaining downforce using Bernoulli's Principle and say the equation for Pressure; P=F/A ?

There is also the variable of "angle of attack" which i understand to be the angle at which the air "hits" the object.

Thanks.