Chapter 5 - Mass and Energy Analysis of Control Volumes - Problems - Page 268: 5-167

$\dot{W}=0.104\ kW$ $D=0.587\ m$

$\dot{m}=\dot{V}\rho,\ \dot{V}=130\ m³/min,\ \rho=1.20\ kg/m³$ $\dot{m}=156\ kg/min=2.6\ kg/s$ $\Delta \dot{KE}=\dot{m}\frac{\mathcal{V}_2^2-\mathcal{V}_1^2}2$ $\mathcal{V}_2=8\ m/s,\ \mathcal{V}_1\approx 0$ $\Delta KE=0.0832\ kW$ $0.8\dot{W}=\Delta \dot{KE}$ $\dot{W}=0.104\ kW$ $\dot{V}=\mathcal{V}\frac{\pi D^2}4$ $D=0.587\ m$