Ron Danon rondanon@gmail.com 0545953935 MSc student, Faculty of Energy Engineering, Technion, 32000 Haifa, Israel David Greenblatt davidg@technion.ac.il 0528314785 Associate Professor, Faculty of Mechanical Engineering, Technion, 32000 Haifa, Israel Wind turbines are a major source of renewable energy with worldwide total installed capacity growing exponentially, but they are at a disadvantage when compared to conventional fossil fuels power plants due to their high capital and maintenance costs. The current research investigates the viability of a new patented concept of wind energy generation. It utilizes active flow control in order to generate oscillatory loads that drive a large pendulum in reciprocating motion. The system comprises a sting-mounted cylinder on a pivot, with 2-DOF motion and counterbalanced by a concentrated mass. The cylinder is equipped with blowing slots, to produce the Coandă effect, which are activated periodically to produce the periodic lift and drag forces that drive the system. This research involves an assessment of the concepts viability by developing an analytical model and using wind tunnel data in a numerical simulation. Slot blowing was produced by means of an air flow controller and wind tunnel data comprised of steady and transient pressure measurements, including three-dimensional effects. These data were used in the simulation to evaluate the performance of a large-scale system. Results indicated power coefficients in excess of 40%, rendering the concept competitive with similar sized wind turbines. In addition to these favorable results, the proposed system can potentially reduce manufacturing, installation and maintenance costs in terms of dollars per megawatts installed. A single relatively simple cylinder replaces typically three blades and maintenance is, in principle, much simpler with the drive-train and generator located close to the ground.
