| | Category | EGPH | P10 | Do Fish Hold the Secret to Hydrokinetic Energy Harnessing? |
| | Abstract | Rationale: In the Spring of 2015, at the Niagara Falls aquarium, I |
| | noticed that when a school of fish changed speed, fish adjusted their |
| | relative position to maintain a regular formation. I observed that fish left |
| | behind struggled to catch up. Soon after, I read a 10-year long DOE- |
| | Harvard-MIT study that investigated the movement of fish behind a |
| | cylinder. It was proven that fish used less energy and flexed their |
| | bodies only slightly when swimming behind a cylinder in a current. |
| | Could a machine be designed to harness hydrokinetic power efficiently |
| | using fish kinematics. I was so fascinated by this that, I contacted the |
| | Marine Renewable Energy Laboratory (MRELab) at the University of |
| | Michigan. They study harnessing hydrokinetic energy using cylinders in |
| | flow-induced vibrations (FIV) in water currents. I proposed to use two |
| | cylinders and change their spacing – like fish do - to study the impact |
| | on harnessing hydrokinetic energy. They agreed and I joined the team |
| | as intern in September 2015. The test-results were phenomenal, |
| | showing an increase in converted power by a factor of 2.6-7.5 when two |
| | cylinders are in synergistic FIV compared to a single isolated cylinder. |
| | Ever since, I have been working in the MRELab to optimize this |
| | converter. Its power-to-volume density is 60,000 times that of wind |
| | farms. Its potential is immense from a renewable energy standpoint and |
| | it is harmless to the environment, since it mimics fish kinematics. |
| | Hypotheses: Based on results I collected and processed for Science |
| | Fair 2016 using two cylinders in synergistic FIV, my hypotheses |
| | pertaining to the power output of three cylinders are: (a) Three tandem |
| | cylinders in synergistic FIV can harness more hydrokinetic energy than |
| | three isolated cylinders. (b) Per cylinder, three tandem cylinders can |
| | harness synergistically more hydrokinetic energy than two cylinders |
| | synergistically. (c) The power converted by three cylinders in tandem |
| | can be optimized with respect to the harnessing damping. |
| | Testing: All tests were conducted in the Channel of the MRELab using |
| | three oscillators consisting of cylinders suspended horizontally by linear |
| | springs in steady flow. Constants: Cylinder diameter, length, mass, |
| | spring stiffness, cylinder spacing. Variable: Flow speed |
| | ≤1.35m/s. Parameter: Harnessing damping. Testing time: 15 |
| | hours. |
| | Data analysis: The displacement history of each cylinder was post- |
| | processed to calculate amplitude and frequency of oscillation, and |
| | harnessed power. Laser flow visualization with high-speed camera |
| | helped understand the interaction between cylinders and wakes. |
| | Results: All three hypotheses were confirmed. Specifically, (a) The |
| | energy harnessed by three cylinders in synergy was 3.4-7 times the |
| | energy harnessed by a single isolated cylinder. (b) Per cylinder, three |
| | cylinders produced 10% more power than two cylinders. (c) By |
| | adjusting harnessing damping power can be optimized. |
| | Bibliography | Liao, J.C., (2007), “A Review of Fish Swimming Mechanics and |
| | Behaviour in Altered Flows”’ Phil. Trans. R. Soc. B, doi:10.1098/rstb. |
| | 2007.2082.Hydrokinetic Energy Technology Assessment Committee; |
| | Board on Energy and Environmental Systems; National Research |
| | Council, “An Evaluation of the U.S. Department of Energy's Marine and |
| | Hydrokinetic Resource Assessments”. |