5. After the performans test of a pump at 800 rpm following data is obtained. | Q (m³/s) | 0.00 | 0.01 | 0.02 | 0.03 | 0.04 | 0.05 | 0.06 | 0.07 | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | H (m) | 41 | 40 | 39 | 37 | 34 | 28 | 17 | 0 | | ? (%) | 0 | 31 | 55 | 71 | 76 | 70 | 50 | 0 | For a certain application we need to select a pump that will deliver 0.04 m³/s of water against a head of 50 m. Possibilities are to use; a) the above pump but operated at a rotational speed other than 800 rpm. Find the efficiency of the pump. Find the power required to run it. b) a pump operated at 800 rpm which is geometrically similar to the pump mentioned above. Find the efficiency of this pump. Find the power required to run it. ( ANS.: a. 73% , 26.88 kW, b. 30.18 kW )
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The data includes flow rate (Q), head (H), and efficiency (η) at various flow rates. Show more…
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