Buckets of various forms are tested on a Pelton wheel, showing the efficiency of each. The efficiency of a wheel being defined by the product of the nozzle, the volumetric, the mechanical, and the hydraulic efficiency of bucket, each efficiency is measured or calculated separately. The hydraulic loss of buckets or the so-called wheel loss is the sum of bucket loss and discharge loss, both of which are separately calculated, and it is shown that the former decreases with increasing speed of rotation of the wheel, while the latter becomes minimum for a certain speed. The hydraulic efficiency of bucket is maximum for a certain ratio of the bucket and jet areas, and is the largest maximum in the neighborhood of the speed, for which the discharge loss is minimum.
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