If you watch the movies, there isn’t much to a wind tunnel. Just a fan and a tunnel, right? The truth is there’s a lot more to it than that, and [ejs13] shows you how you can make a small tunnel with some basic supplies. One of the requirements for a useful tunnel is to have laminar flow — that is, flow in uniform layers with little, if any, mixing. This tunnel achieves laminar flow using an array of soda straws to direct the flow. In fact, there are 150 straws in total. You can see a short clip of the wind tunnel in action below.
The rest of the parts are easy, too. A computer fan provides wind, and there’s a little bit of wood and acrylic. You’ll notice in the video that you can easily see the airflow. That’s thanks to a light source, some water, and a bit of dry ice.
We imagine you can scale this design up with bigger fans and, of course, more straws. The acrylic is to provide a window so you can see inside. Glass would probably work, too. Overall, this would make a great class project, along with creating some wings or small models of planes or cars.