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Typical performance curves for a centrifugal pump, tested with three different impeller diameters in a single casing, are shown. Specify the flow rate and head produced by the pump at its best efficiency point with a 12-in.-diameter impeller. Scale these data to predict the performance of this pump when tested with 11-in. and 13-in.-diameter impellers. Comment on the accuracy of the scaling procedure.
P10.26
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