Kelley Fletcher Dustin Eseltine Ryan Sargent Group 5

The Need: –With the constant rise in cost of non-renewable energy sources, alternative sources of renewable energy are becoming more important –Energy produced by ocean waves is constant. –Constant energy = infinite supply –Infinite supply = Lower Cost Objective: –Design a device that converts ocean waves into useable electrical energy

Heaving Floats –Rise and fall of waves causes float to rise and fall creating energy. Pitching Device –Rise and fall or waves causes the float to pitch –Pitching motion is then converted to energy. Wave Direction

Oscillating Water Column –Waves cause a pressure change inside a chamber. –Oscillating air or water drives energy device (eg. turbine) Surge Device -Ocean Waves flow into narrowing chamber -Water forced into reservoir -Energy flows through turbine back into ocean.

Archimedes Wave Swing Passing Waves causes the top chamber to rise and fall Rise and fall of top chamber cause pressure difference inside device Pressure difference runs hydraulic motor

Oscillating Water Column Waves coming into coast cause rise and fall inside chamber Rise and fall of water in chamber pushes air through turbine. Dual cycle, needs bi-directional turbine

After researching current designs the following design goals were created: –Not a coastal based system. –Not a hydraulic based system. –Make the system scalable. –Design system to be relatively safe from natural occurrences such as storms

D-Rings attach buoy to anchoring cables. The three cables from the buoy are attached to the single cable using a turnbuckle. This system allows for minor height adjustments after installation. Single cable attaches to buried concrete anchor.

Passing waves cause a differential pressure change in a submerged chamber. The pressure change causes an airflow through a nozzle. The airflow is used to run a Pelton Turbine. ½-wave = 1stroke 2 strokes in a cycle: –Compression –Suction CompressionSuction

L= Wave Length H= Wave Height D= Water Depth Note: One wave = Crest to Crest –or- Trough to Trough Particle depth is considered a negative value Design calculations based upon ½wave

Underwater particle velocities are related to: Wave Height(H) Wave Length(L) Water Depth(d) Particle depth(z) Wave Period(T) Deep Water Circular velocity profile Shallow-Transitional Elliptical velocity profile Particle Velocity Equations

Equation of State – P 1 V 1 = P 2 V 2 Bernoulli’s Equation Substituting for Velocity -Bernoulli’s Eq. Allowed P site to be solved. -Once P site was known the particle velocity equations were substituted for surface and site velocities.

Volumetric Airflow - Once P site was known, volumetric airflow could be derived. Volumetric Airflow – Q-Bar - Integrating Q gave us Q-bar. Allowing t to be replaced by T/2 (one cycle time.) Q-Bar = Volumetric air flow for one cycle

Using the National Oceanic and Atmospheric Administration’s website buoy #46212 was chosen. Data was downloaded from the NOAA website for Wave Height, Wave Period, and Atmospheric Pressure.

Water data was compiled using excel, equations, and buoy data. Average values were tabulated for each day and then for each month.

Volumetric airflow data compiled from buoy data Average values were compiled daily, monthly, and then yearly. Yearly values were used for turbine calculations. Daily values allowed the group to calculate the turbines power output for any day of the year.

Double Acting Turbine Bi-direction turbine Possibly self starting Wells Turbine Bi-directional Turbine Not self starting Blades symmetric to rotation axis Paddle Wheel Design Simplistic in operation and construction Self starting

Advanced paddle wheel design ”Buckets” increase amount of energy extracted from jet stream Scalable design Self Starting Turbine is up to 91% efficient

Volumetric air flow was used to calculate the following: Pitch Circle Diameter (PCD) Jet Diameter Jet Area Jet Velocity Pitch Circle Diameter - PCD determines turbine size Jet Velocity -Jet diameter = Nozzle Diameter Jet area = cross sectional area of nozzle -Jet velocity is determined from average flow rate and jet diameter. Jet Diameter

At 100% efficiency and Flow the Turbine Produces Watts Normal overall system efficiency for Pelton Turbines is 60% About 40 Watts would be produced at 60% efficiency Generator is only capable of handling 18 Watts of Continuous power. 12 volts x 1.5 amps Turbine Power Output -Shaft work = Theoretical power Output

Using COSMOSWorks, material data, and calculated values a brief analysis was completed. Turbine Max. Deflection – in. Max. Stress PSI Turbine Blades Max. Deflection – 4.2e-04 in. Max. Stress – 56.69PSI Safety Factor Infinite Life – SLA Model

Fully scalable turbine system Submerged design protects device Power output of one “buoy” = 18 Watts

1) Build a prototype model 2) Prototype would be tested for: Turbine efficiency, Air vs. Water Stability Actual power output Actual volumetric flow rate 3) Safety mechanisms may need to be designed to prevent water entering system. The prototype design concept is complete. The next steps in the project are:

Questions? Thank you for your time.