The following data refer to a Pelton wheel: the bucket angle b=165°, the coefficient of discharge for the nozzle Cv = 0.98, the friction coefficient k = 0.2. Assume that the optimum speed ratio differs from 0.5 as a result of losses due to windage and bearing friction, which are proportional to the square of the rotational speed (take the proportionality constant equal to 0.2), obtain a formula for the optimum speed ratio, hence calculate it for the above given data and also calculate the maximum overall efficiency, in percentile.

The following data refer to a Pelton wheel: the bucket angle b=165°, the coefficient of discharge for the nozzle Cv = 0.98, the friction coefficient k = 0.2. Assume that the optimum speed ratio differs from 0.5 as a result of losses due to windage and bearing friction, which are proportional to the square of the rotational speed (take the proportionality constant equal to 0.2), obtain a formula for the optimum speed ratio, hence calculate it for the above given data and also calculate the maximum overall efficiency, in percentile.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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