Hydraulic Motors: Turbines and Pressure Engines

Abstract

THE essential detail which lifts the mere water-wheel to the rank of a turbine consists, according to the author, in some arrangement for directing the water over the buckets in the most advantageous manner, instead of allowing the water merely to follow its own course. Again, in a water-wheel only a small part of the wheel is really at work at a time, the buckets of the remaining part being empty; while a turbine is arranged, as a rule, with a vertical axis, and all parts of the wheel are simultaneously taking their fair share of the work. In this respect there is a great resemblance and analogy to the distinction between the two chief instruments of ship propulsion by steam—the paddle-wheel and the screw propeller. In the paddle-wheel only a few of the floats act on the water at time; while in the screw propeller, completely submerged, all parts are equally at work, implying a great saving of weight in the propelling instrument. Mr. Thornycroft, with his turbine propeller, is able to emphasize this economy of weight still further, and, but for difficulties of going astern not yet surmounted, would be able to save considerable weight and space in sea-going steamers with this contrivance.

Hydraulic Motors: Turbines and Pressure Engines.

By G. R. Bodmer “The Specialist's Series.” (London: Whittaker and Co., 1889.)