Prob-5 The pressure rise, Ap across a centrifugal pump from a given manufacture can be expected to depend on the angular velocity of the impeller w, the Diameter D, of the impeller, the volume flow-rate Q, and the density of the fluid, p. By using the method of repeating variables show that Ар pw² D² Q @D³ A model pump having an impeller diameter of 0.200 m is tested in the laboratory using water. The pressure rise when tested at an angular velocity of 40z rad/sec is shown on the graph. What would be the pressure rise for a geometrically similar pump with an impeller diameter of 0.30 m used to pump water operating at an angular velocity of 80л rad/sec and at a flow rate of 0.070 m³/s? Sol: 40 40 30 (kPa) Apm 10 0 0 0.02 0.04 Model data =40лrad/s D = 20 cm 0.06 2m (cubic meters per sec) 0.08