... ABSTRACT To utilize effectively tidal stream, the authors have developed a counter-rotating type tidal stream power unit composed of tandem propellers and a peculiar generator with double rotational armatures. This paper prepares a prototype power unit with a synchronous type generator...

... Abstract A counter-rotating type horizontal-axis tidal stream power unit has a number of attractive features, for instance, cavitation can be suppressed well owing to decrease the individual rotational speed in keeping the relative rotational speed same as the single propeller speed...