CJT Home, Engineering Department, Faculty of Science & Technology, Lancaster University, Lancaster, UK.
Lancaster University, Doctor of Philosophy, 2012
Supervisor: C.J. Taylor
A panel based method has been used to generate aerofoil performance data of standard profiles and multi-element profiles for a relative comparison of lift and drag coefficients. This data has then been applied to a cross-flow turbine model to assess the potential performance gain. Scale testing of models is used to validate results and the thesis includes the design and build of appropriate apparatus to facilitate this testing. Results demonstrate that the addition of a trailing edge plain flap increases the peak lift to drag ratio by 26% in comparison to a single blade of equivalent chord. The gains predicted for a turbine are in excess of this due to an increase in the tangential force vector, along with an increase in the range of angles for which the blade is active for. A true performance comparison is difficult to achieve given the complexity of the downstream turbine behaviour but an efficiency of 48% has been calculated for a multi-elements rotor. The addition of a leading edge slat for the combinations tested has not been found to provide performance gain relative to a symmetrical profile. It is recommended that experimental testing be completed to fully understand the conditions at the trailing downstream edge of the turbine.
Updated 31st October 2017. CJT Home Page