The performance characteristics of a certain centrifugal pump having a 9-in.-diameter impeller and operating at \(1750 \mathrm{rpm}\) are determined using an experimental setup similar to that shown in Fig. 12.10. The following data were obtained during a series of tests in which \(z_{2}-z_{1}=0, V_{2}=V_{1}\), and the fluid was water.

Based on these data, show or plot how the actual head rise, \(h_{a}\), and the pump efficiency, \(\eta\), vary with the flowrate. What is the design flowrate for this pump?

Figure 12.10

Transcribed Image Text:

Q(gpm) P2 - P (psi) Power input (hp) 20 40 60 80 100 120 140 40.2 40.1 38.1 36.2 33.5 30.1 25.8 1.58 2.27 2.67 2.95 3.19 3.49 4.00