Figure P3.52 shows a duct for testing a centrifugal fan. Air is drawn from the atmosphere ( \(p_{\text {atm }}=14.7 \mathrm{psia}, T_{\mathrm{atm}}=70^{\circ} \mathrm{F}\) ). The inlet box is \(4 \mathrm{ft} \times 2 \mathrm{ft}\). At section 1, the duct is \(2.5 \mathrm{ft}\) square. At section 2, the duct is circular and has a diameter of \(3 \mathrm{ft}\). A water manometer in the inlet box measures a static pressure of -2.0 in. of water. Calculate the volume flow rate of air into the fan and the average fluid velocity at both sections 1 and 2. Assume constant density.

Figure P3.52

Transcribed Image Text:

2 in. water Throttling Inlet box plug Fan (1) (2)