Development of Counter-Rotaing Type Machine for Water Power Generation. 1st Report. Counter-Rotating Type Generator and Axial-Flow Runners.

Abstract

This paper proposes the counter-rotating type machine for water power generation which is composed of the two-stage runners and the double rotors in the generator, and discusses the performances and internal flow conditions based on the experiments for the trial model. The maximum output power is obtained at the same counter-rotational speeds as designed, but such speeds differ from the maximum efficiency point. In the individual runner, the maximum output power of the rear runner is slightly less than that of the front runner, but the efficiency is overall good though the inlet flow condition of the rear runner is disturbed by the front runner. The flow conditions around the runners suggest the further improvement points for the runner profiles.