A Tale of Two Tanks
Science Storms originally had 2 large wave tanks planned – the long, thin trough tank that you see in the exhibit today as well as a wider so-called surface tank, which has the aspect ratio of a football field. The reason for two different tanks is that they demonstrate different kinds of physics: trough tanks are good for modeling what happens when a wave moves across open water; surface tanks are good for modeling what happens when a wave lands on the shore.
The surface tank was envisioned to be hanging overhead, cantilevered off the balcony. That posed a considerable engineering challenge to have not only the weight of the tank, water and motors but also having the load be dynamic, that is the water moving around would constantly change how the weight was distributed. In addition, as the exhibit concept evolved and content research progressed, the exhibit team decided to focus the tsunami area on the concept that waves move energy from one place to another. That content decision made the trough tank the priority since it more clearly demonstrated the principle.
Ultimately, the exhibit team took the idea of having tanks cantilevered off the balcony and applied that to the concept to the ripple tank exhibit. After audience testing with a small tabletop ripple tank, they noticed that people wanted to look at the shadows on the table surface below the tank instead of directly in the tank itself. Once the decision to focus on one large trough tank on the main floor instead of two was made, the ripple tanks took to the skies.