| 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”. |