An axial fan operating at \(1000 \mathrm{rpm}\) has the characteristics shown in Fig. P12.42. It delivers \(15{ }^{\circ} \mathrm{C}\) atmospheric air through a 50-cm I.D., galvanized, sheet-metal, horizontal duct having a length of \(175 \mathrm{~m}\) and seven \(90^{\circ}\) long-radius elbows. For constant air density what is the flow rate if the duct discharges to the atmosphere?

Figure P12.42

Transcribed Image Text:

Static head (cm H2O) 20 20 15 10 5 0 0 50 100 150 200 Air flow rate (m/min)