Tethered undersea kite (TUSK) systems use tethered, rigid-winged kites (or gliders) moving at high speed to extract energy from an ocean, tidal or river current. A turbine is mounted on the glider in one TUSK concept. In a second concept, hydrodynamic forces on the glider are used to tension and unwind the flexible tether which turns a generator shaft located on a surface buoy. TUSK systems have potential advantages over conventional marine turbines. TUSK systems will be able to generate energy with smaller, less costly systems at locations where current speeds are too low to make marine turbines feasible. The main reasons for this are three-fold; 1) the glider can move in high-speed cross-current motions over large swept areas to greatly increase power output, 2) TUSK systems eliminate the need for large diameter turbines and costly support structures, and 3) TUSK systems are easier to maintain.
TUSK systems use the same physical principles and modes of operation as airborne wind energy (AWE) systems where flexible kites or rigid wings are used to extract power from higher-altitude winds. While AWE systems have been extensively analyzed, few technical studies on TUSK systems exist. In this talk the operation and basic theory for TUSK systems will be reviewed. An overview of results from an integrated study of TUSK systems at WPI will be presented including; TUSK design studies, modeling of winged glider-tether dynamics, glider control studies, and computational fluid dynamic (CFD) simulations. Development of a low-cost, kite-powered water pump (in air) for use in developing nations through undergraduate design projects at WPI will also be briefly summarized.
Prof. David J. Olinger has been a member of the Mechanical Engineering Department and Aerospace Engineering Program at WPI since 1990. His research interests have included fluid-structure interactions problems focused on using nonlinear chaos theory to study vortex-induced vibration, experimental fluid dynamics, and low-speed aerodynamics. More recently he has worked in the area of renewable energy focused on both simulation and physical modeling of airborne wind and tethered hydrokinetic energy systems. His teaching interests within the aerospace engineering program include aerodynamics, thermal-fluids, aircraft design, and renewable energy.