A centrifugal pump is installed with a static suction lift of $h_s = 4.5\text{ m}$. The suction pipe friction loss is $h_{fs} = 0.60\text{ m}$. The atmospheric pressure head is $10.13\text{ m}$ and water vapor pressure head at operating temperature is $0.24\text{ m}$. The Net Positive Suction Head Available ($NPSH_A$) at the pump inlet is ________ $\text{m}$ (round off to two decimal places).
Answer Key:
4.79
Step-by-Step Solution & Explanation
The Net Positive Suction Head Available is given by:
$NPSH_A = \frac{P_{atm}}{\gamma} - \frac{P_v}{\gamma} - h_s - h_{fs}$
Given $\frac{P_{atm}}{\gamma} = 10.13\text{ m}$, $\frac{P_v}{\gamma} = 0.24\text{ m}$, $h_s = 4.5\text{ m}$, and $h_{fs} = 0.60\text{ m}$:
$NPSH_A = 10.13 - 0.24 - 4.5 - 0.60 = 4.79\text{ m}$