Mechanical Engineering Department
BS in Mechanical Engineering
To prevent salp (jellyfish) from entering Diablo Canyon Power Plant’s intake pipes, and ultimately having the plant shut down as a result, an air bubble curtain is anchored along the ocean floor for the duration of the salp swarm to create a barrier that prevents the salp and other debris from entering the intake. The curtain consists of four large air compressors connected to four parallel pipes with holes strategically drilled at various places along the length of the pipe. When the air compressors are turned on, a torrent of bubbles are shot out from the pipes which create a current which deters the salp from floating into the intake. As the ocean floor shifts with the current and tide, the pipes becomes unlevel and do not produce an adequate barrier of bubbles across the length of the pipe. To improve the bubble curtain, our team was tasked with creating a self-leveling anchor system to work with the existing air bubble curtain pipes. Over the course of the last academic year, we designed, built, and tested a model sized prototype of an anchoring concept that would keep the bubble curtain pipes level. The final design suspends the bubble curtain pipes from buoys. The concept uses the surface of the water to remain level, while a long tether to a ground anchor keeps it from floating freely. Through testing, we determined this design stays level independent of change in floor elevation. However, the effectiveness is dependent on the tide, and works best at low tide and in water with a low tide greater than 20 feet. We recommend designing this system for deeper sections of the intake bay, and implementing it to allow a constant upward slope in the bubble pipe. Before building a complete system, we recommend constructing and testing a partial system to insure it behaves as expected and withstands full-scale ocean conditions.