Measurements were made of the static pressure distribution along the surfaces of the blades of a Francis turbine runner operating near its optimum efficiency and at the extremes of unit speeds where incidences stretched from + 80° to −54°. The paper describes equipment and experimental procedure aimed at accuracy and compares the results against theoretical predictions furnished by computer programmes available at GEC Power Engineering Ltd. The correlation between curves was good in the optimum efficiency region and it was concluded that the mathematical model was a valuable aid to design and development and, subject to some restrictions, could reduce the need for scale models.
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