Because
tidal current turbines are still in the early stages of development,
little design information exists, and much of this information is
proprietary. In order to gain a fundamental understanding of
any previous knowledge on the topics of the hydrodynamics, design
atributes, and testing techniques of tidal turbines, we have read all
the public documentation that we came across. To supplement this
research, we also had the guidance of our professors and others from
both the University of Maine, and the Maine Maritime Academy. These
sources include:Michael "Mick" Peterson,
Ph.D. (UMO) - General guidence on mechanical engineering topics
Richard Kimball, Ph.D (MMA) - Expert on marine hydrodynamics and propeller design/testing
Steve Rioux, Tool/Die Maker (UMO) - Guideance with machine tool processes during build phase
Stig Callihan, BS Electical Engineeing (UMO) - Assistance with electrical applications
Ronnie Oliver, BS Mechanical Engineeing (UMO) - OpenProp source code
Richard Kimball, Ph.D (MMA) - Expert on marine hydrodynamics and propeller design/testing
Steve Rioux, Tool/Die Maker (UMO) - Guideance with machine tool processes during build phase
Stig Callihan, BS Electical Engineeing (UMO) - Assistance with electrical applications
Ronnie Oliver, BS Mechanical Engineeing (UMO) - OpenProp source code
Our research led to the creation of various reports, design matrixies and presentations, which are show below baised on their topic.
TIDAL TURBINE DESIGN
Initial reseach was on the subject of the design of a tidal turbine. This reseach was based off of several previous studies, and included the topics of ancering systems, measurements standards and design conciderations. From these documents, we compiled much of the important information into a single Tidal Turbine Design Research Document. We also built a Tidal Turbine Design Matrix to weigh the advantages and disadvantages of several styles of turbines and determine which type our test bed was to be designed to test.
Turbine installation methodsSource: Fraenkel P.L., 2002,
“Power from Marine Currents,” Proc Instn Mech Engrs, Vol 216, Part A.
The design of the prop itself would be done with OpenProp; an opensource propeller design optimization program initiated by MIT. With the help of Professor Rich Kimball, Ronnie worked on converting the existing OpenProp source code (initially intended to be used as optomization software for the design of ship propellers) to optmize tidal turbine design. The OpenProp code takes in flow parameters and a few prop size guidelines and creates a three dimentional prop design. This design can be taken directly from the program through an STL file and instantly created through one of various rapid prototyping methods.
TESTING FACILITY
Testing was performed in a tow tank. The tow tank is a 100 foot long by 4 foot wide by 4 foot deep pool of water with an overriding carriage system. The carriage traverses along the lenght of the tow tank by means of a truck and rail (much like a roller coster) and cable drive system and is capable of speeds up to 2.5 meters per second (4.9 knots). This carrage is what allowed us to control the velocity of the water past the turbine (equal to the velocity of the turbine through the water and the carriage speed) and obtain the neccisary data. The tow tank is housed in the Aquaculture Research Center at the Univeristy of Maine, Orono, Maine. A look down the lenght of the tow tank.
For a more visual discription of the basis of this deign project, consider these two power point presentations: