My senior design project focused upon the development of a small scale water turbine that could potentially be used in underdeveloped areas with high rainfall or large runoff systems. The device would harvest the energy potential of the water flow relying on a low velocity but high pressure flow caused by collection of the water within a vertical gutter system. Therefore the product focused on a Francis turbine design in which a volute (initially of uniform diameter) feeds water into a horizontally supported impeller. This impeller is attached to an electric motor via an aluminum shaft. Due to the pressure difference on either end of the turbine blades caused by the water height within the gutter system, the impeller begins to rotate which in turn rotates a DC generator.
The tasks I spearheaded included the design of the product as well as the structure on which it would be placed. The most difficult component was the volute (see Figures 2-4). The volute is a converging pipeline that directs and maintains the pressure of the fluid as it approaches the impeller. With an extremely strict budget, metal casting and 3D printing were not an option due large size increasing cost. Rather, for proof of concept testing, a polyurethane resin was cast. The negative was created out of clay and then removed once the resin cured.
After manufacturing and testing, the harvester was deemed functional but did not meet the desired output power.
RAIN WATER ENERGY HARVESTER
Project: Water Energy Turbine (Senior Design)
Timeline: 9 months (Sept. 2012 – May 2013)
# of participants: 5 People
Job:
Lead Design Engineer, Co-Project Manager
Project Requirements:
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Diminish reliance on non-renewable fuel sources
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Provide affordable energy to remote areas
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Low cost and low required changes to existing infrastructure
Figure 1. CAD model ISO view with components callout
Figure 3. Resin cast volute with mold negative removed and guide vanes installed
Figure 2. CAD model Top view of the volute with impeller and guide vanes
Figure 5. 3D Printed Impeller for Francis Turbine
Figure 6. Completed energy harvester assembly with multimeter to measure output voltage
Figure 4. Volute clay negative (left), and submerged negative in resin (right)