Concept explainers
Liquid ethanol (p = 783 kg/m3) at a pressure of 230 kPa enters a 10-cm-diameter pipe at a rate of
2.8 kg/s. Ethanol leaves the pipe at 100 kPa at 15 m above the inlet level. Take the correction factor to be 1. If the diameter of the pipe at the exit is 12 cm, the irreversible head loss in this pipe is
(a) 0.95 m
(b) 1.93 m
(c) 1.23 m
(d4.11 m
(e)2.86m
The head loss in the pipe is
Answer to Problem 136P
The head loss in the pipe is
Explanation of Solution
Given information:
The pressure at the entry is
Write the expression for the Bernoulli Equation
Here, pressure at entry of the pipe is
Write the expression for the mass flow rate.
Here, at the entry
Write the expression for the area at the entry of pipe.
Here, diameter at the entry of the pipe is
Write the expression for the area at the entry of pipe.
Here, diameter at the exit of the pipe is
Write the expression of the continuity equation.
Calculation:
Substitute
Substitute
Substitute
Substitute
Substitute
Conclusion:
The head loss in the pipe is
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Chapter 5 Solutions
Fluid Mechanics: Fundamentals and Applications
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