Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636688
Title: A design study for an experimental horizontal axis wind turbine
Author: Woollard, M. G.
Awarding Body: University College of Swansea
Current Institution: Swansea University
Date of Award: 1980
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Abstract:
A five metre diameter, horizontal axis, variable pitch wind turbine has been designed and built to permit a long term investigation into the suitability of wind turbines for large scale power generation, by facilitating the study of many aspects of operation including aerodynamic performance, control characteristics and stress measurements. Vortex and blade element theories have been used and compared for estimating the rotor aerodynamic behaviour, and corrections for circulation reduction caused by the finite number of blades have been applied from theories originally suggested by Goldstein, Theodorsen and Prandtl. An iterative computer program has been developed which uses blade element theory to design an optimal rotor, predict the nature of the flow and enable the determination of the rotor stability derivatives and transfer functions. Aerodynamic data at relevant incidences and Reynolds numbers are interpolated from a data matrix. The aerodynamic study was extended to provide a stress analysis procedure for the rotor blades which were designed to give high efficiencies at a tip speed ratio of 5. Constructional techniques were developed to enable the complex optimal blade shape to be fabricated in glass and carbon reinforced polyester. The blades were mounted on an aircraft propellor variable pitch unit, modified for the wind turbine application. As a parallel study, a technique was developed for testing a model turbine in a water tank. Performance parameters were continuously monitored by a computer, enabling the characteristic to be determined over a wide range of operating conditions. This method has some advantages over wind tunnel tests. Initial results taken in the fixed pitch mode have identified several problem areas in performance measurement including spatial and time variation in measured wind speed and transient torque effects in the rotor. The high degree of scatter encountered in the data may be reduced by improved measurement technique and statistical analysis.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.636688  DOI: Not available
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