Part I - Inventing the Future
The Wind Tunnel
|The original wind tunnel no longer exists, but a replica was built for
display in The Franklin Institute's Aviation Hall. The replica was built
carefully to match the original dimensions and materials. Orville
Wright himself was present at the 1934 opening of Aviation Hall to see
the exhibit. (An interesting sidenote is that
Orville was photographed standing
with Amelia Earhart in the Museum that
day. Orville is on the left, as you look at the photo.
The third person is an official of The Franklin Institute. They are
looking at a bust of Wilbur.)
Rather than providing photographs of the replica, which do not capture the excitement of the wind tunnel, three-dimensional models have been created. Exact measurements and material specifications were used to render these images of the wind tunnel. They are, effectively, next generation replicas of the original.
In this side view of the tunnel, notice the grey metallic cone on the right. The blades of the fan rotated in the cone. A metal rod attached to the fan blade was turned by a pulley system. The bottom of the pulley was mounted on a wooden block, as shown, and the top reached up to the rafters.
This top view of the tunnel shows the location of the glass window through which they watched the reaction of their airfoils to differing wind speeds. To test a different airfoil, they simply removed the window and exchanged airfoils on the balance inside.
|This rendering shows the interior parts of the tunnel. Imagine you are standing at the far end of the tunnel, peeking through the metallic cone, straight along the rod that turned the fan. Beyond the blades, notice the metal grid that was used to even the flow of the wind. Now, the current of wind is inside the wooden box, blowing on the balance which is positioned on the base of the box.|
These four views of the lift balance show the careful design used to test the airfoils. The balance was mounted on the floor of the wind tunnel and, then, an airfoil was placed on the balance for testing. The movements of the parts were measured carefully and recorded. The original balance, hand-crafted by Wilbur and Orville Wright exists today in the collection at The Franklin Institute Science Museum. Its delicate state makes it somewhat fragile. Therefore, these renderings were created from exact measurements in order to provide the best view possible for public audiences.
Animations of the wind tunnel are available to show the operation of the
replica. Several versions of the same animation are available.
There is no sound
in the interest of smaller file sizes. The animation begins with a spinning,
outside view of the tunnel. Then, the pulley turns the rod which causes
the fan blade to spin. (Two small streamers have been added for the
purpose of visualizing the movement of air. There is no evidence that
the Wrights did or did not use streamers in their original tunnel.) One
wall of the tunnel "disappears" briefly, allowing a full view of the
interior of the tunnel.
Today's wind tunnels are built on the same principles that the Wright
Brothers used. The Parts of
a Wind Tunnel work together to create a steady stream of strong wind.
You can Make a Simple Wind Tunnel
yourself to understand how the parts work together.
Now, back to the story as
[ First Flight | Part I | Part II | Part III | Part IV ]