The Gorlov helical turbine (GHT) is a water turbine evolved from the Darrieus turbine design by altering it to have helical blades/foils. It was patented in a series of patents from September 19, 1995[1] to July 3, 2001[2] and won 2001 ASME Thomas A. Edison Patent Award. GHT was invented by Professor Alexander M. Gorlov of the Northeastern University. The physical principles of the GHT work[3] are the same as for its main prototype, the Darrieus turbine, and for the family of similar Vertical axis wind turbines which includes also Turby wind turbine Quietrevolution wind turbine Urban Green Energy. GHT, turby and quietrevolution solved pulsatory torque issues by using the helical twist of the blades.
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