To start off, we knew the basics of wind tunnel. A air source that is compressed, increasing the speed allowing for various objects to be tested for aerodynamics and air resistance. A source of inspration for making the tunnel was another Instructable that was made previously by user Goalieguy (http://www.instructables.com/id/Cardboard-Wind-Tunnel/
be sure to check it out!).
We also used NASA as a resource into the design of the tunnel.
Now that the tunnel design was set, we had to come up with a way to generate smoke. Ian thought up of the idea of using a pump and a jar and that can be seen on the bottom right side of the diagram. Pretty smart idea I gotta say.
Now how does a wind tunnel work? Well the physics behind it are based off the work of Daniel Bernoulli, a Swiss physicist. Many might remember him from the equation that you learned in physics back in high school of constant= P + 1/2 p v^2 + p g h
. An equation he helped contribute to, the continuity expression in physics of A1V1=A2V2. This provides the foundation of wind tunnels by showing how if you decrease the cross sectional area, your speed subsequently increases. In the case of this specific tunnel that was made, the speed increased by a factor of 3.5 from leaving the fan to being compressed by the contraction section.