Question

An impulse turbine like a Pelton’s turbine is __________________________

(a) an open body exposed to the atmosphere

(b) a closed body not exposed to the atmosphere

(c) a partially open and partially closed body

(d) depends on the design requirements

This question was posed to me in final exam.

The query is from Hydro Electric Power topic in division Hydro Electric Power of Irrigation Engineering

Answer 1

Right option is (a) an open body exposed to the atmosphere

The best explanation: The water through a contacting nozzle or by guide vanes is made to strike on a series of buckets. The wheel revolves free in the air and the water is in contact with only a part of the wheel at a time and the pressure is atmospheric. A casing is provided in order to prevent splashing and to guide the water discharged from the buckets to the tail-race.