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To obtain maximum hydraulic efficiency of pelton turbine, blade velocity should be ___________ Times the inlet velocity of jet.

To obtain maximum hydraulic efficiency of pelton turbine, blade velocity should be ___________ Times the inlet velocity of jet. Correct Answer Half

Hydraulic efficiency is defined as ratio between power given by water to runner of turbine and to the power supplied by water at inlet of the turbine. This efficiency will be maximum when differentiating it with “u” and it is obtained as u=v/2.

Related Questions

Consider the following statements in connection with hydraulic turbines: 1. The Kaplan turbine is a radial flow turbine in which the guide vane angles as well as the runner vane angles are adjustable. 2. Francis and Kaplan turbines are provided with draft tubes which carry water from exit of runner to tail water to increase the gross head across the turbine. 3. The parts of turbines susceptible to cavitation are the guide vanes and runner vanes – drastically reducing the turbine efficiency. 4. The specific speed of a 4-jet Pelton turbine will be 28 if the specific speed of a single-jet Pelton turbine is 14. Which of the above statements are correct?
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Simplify the value of $$\frac{{{\text{0}}{\text{.9}} \times {\text{0}}{\text{.9}} \times {\text{0}}{\text{.9 + 0}}{\text{.2}} \times {\text{0}}{\text{.2}} \times {\text{0}}{\text{.2 + 0}}{\text{.3}} \times {\text{0}}{\text{.3}} \times {\text{0}}{\text{.3}} - {\text{3}} \times 0.9 \times {\text{0}}{\text{.2}} \times {\text{0}}{\text{.3}}}}{{{\text{0}}{\text{.9}} \times {\text{0}}{\text{.9 + 0}}{\text{.2}} \times {\text{0}}{\text{.2 + 0}}{\text{.3}} \times {\text{0}}{\text{.3}} - 0.9 \times {\text{0}}{\text{.2}} - {\text{0}}{\text{.2}} \times {\text{0}}{\text{.3}} - 0.3 \times 0.9}} = ?$$
$$\frac{{38 \times 38 \times 38 + 34 \times 34 \times 34 + 28 \times 28 \times 28 - 38 \times 34 \times 84}}{{38 \times 38 + 34 \times 34 + 28 \times 28 - 38 \times 34 - 34 \times 28 - 38 \times 28}}$$            is equal to = ?
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