A dynamic computer model of a turbine was developed in MATLAB in order to study the behavior of vertical axis wind and hydrokinetic turbines with articulating foils. The simulation results corroborated the findings of several empirical studies on various turbines in both wind and water currents. The model was used to analyze theories of pitch articulation and to inform the discussion on turbine design. Several new patents and proposed configurations were tested. Simulation results showed that pitch articulation allowed Darrieus-style vertical axis wind turbines to start from rest. The tip speed ratio was found to increase rapidly, carrying the turbine into very fast rotational velocities. The simulations revealed a region of high efficiency for wind turbines at high rates of rotation and demonstrated the advantages of using a dynamic generator load. The model was also used to study the behavior of hydrokinetic turbines in restricted environments like irrigation canals – a situation where the Betz analysis is not suitable. Further study showed that when a turbine is inserted in a channel, the resulting blockage causes the development of potential energy in the form of hydraulic head upstream of the turbine. The model was used to predict the efficiency of hydrokinetic turbines in this situation and the water level rise that would occur upstream.
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