You have the following data set from a pump that is operatin

You have the following data set from a pump that is operating at 1725 rpm with a 16 cm diameter impeller: To match your current system, you plan on changing both the impeller and the operating speed. What impeller diameter and pump speed should you specify so that it will operate at its best efficiency point with a pump head and a flow rate as close as possible to 15 m and 7.5 Lpm respectively? Assume the best efficiency point for the pump at the conditions in the table occurs at a volumetric flow rate of 20 Lpm.

Solution

a) 17.3N @ 87.1° b) 108.3N