Pitch angle effect for horizontal axis river current turbine

The horizontal hydro-kinetic river current turbine power technology is one of the renewable decentralized power services potential in delivering energy for the communities in remote regions inaccessible by electricity connection. The utilization of the kinetic mechanism makes the application of the turbine less environmentally detrimental and more extensively available than the conventional hydro-energy which uses the level differences. However, the only kinetic mechanism of the turbine possibly brings the application to be less economically attractive since the low typical river velocity. This highly possibly results in the low turbine performance. Thus to make the turbine application economically feasible, in the design turbine stage, a preliminary figure on an efficient design is paramount. In order to contribute in satisfying this requirement, this study investigates the effect of the variation of the pitch angle, one of the design turbine parameters, on the horizontal axis river turbine performance. The investigation is conducted by a parametric study with the mathematical model of the Blade Element Momentum theory. The results indicate that the increasing of the pitch angle initially enhances the performance. However, too much pitch angle enhancement results in low performance and reduces the rotation operation which in turn it requires a high gearing ratio of the transmission system. This study also attempts to discuss the philosophy behind the results of the investigation, relating the phenomena to the hydrodynamic behaviour. (C) 2012 Elsevier B.V ... Selection and peer-review under responsibility of Bin Nusantara University