Effect of the Utilizing Savonius Machine as Auxiliary Starting Device on the Performance of Darrieus Machine

Abstract

In the present study, the two installation methods in combining Darrieus machine to Savonius machine were applied. First, Savonius machine was directly mounted to the main shaft of Darrieus machine and another one it was mounted to the main shaft via one-way bearing. The result shows that the self-starting ability of Darrieus machine could increase of about 60% by combining it with drag device such as Savonius machine. However, the net power extracted by this combination is significantly decrease. In the combination of Darrieus-Savonius machine where the Savonius was directly mounted on the main shaft without one-way bearing gives power reduction 53%, while in the combination of Darrieus-Savonius machine where the Savonius was mounted on the main shaft with one-way bearing gives power reduction of about 29%. Savonius machine mounted to the main shaft via one-way bearing gives relatively lower impact in power extraction reducing of Darrieus machine instead of Savonius was directly mounted to the main shaft without one-way bearing. As conclusion that the combination of Darrieus-Savonius machines should be addressed to improve the starting ability only, it should not be addressed to improve the power extraction capability of Darrieus machine.