Water at
The required pumping head.
The pumping power required to maintain the flow.
Answer to Problem 137P
The required pumping head is
The pumping power required to maintain the flow is
Explanation of Solution
Given information:
The temperature of the water is
Write the expression for the cross-sectional flow area of the pipe 1.
Here, the diameter of the pipe one is
Write the expression for the velocity of the liquid.
Here, the discharge through the pipe is
Write the expression for the Reynolds number.
Here, the dynamic viscosity of water is
Write the expression for the relative roughness value.
Here, the equivalent roughness of the pipe is
Write the expression for the head of pipe 1.
Here, the friction factor is
Write the expression for the cross-sectional flow area of the pipe second.
Here, the diameter of the pipe second is
Write the expression for the velocity of the liquid for pipe second.
Write the expression for the Reynolds number.
Write the expression for the relative roughness value.
Here, the equivalent roughness of the pipe is
Write the expression for the head of pipe 2.
Here, the length of the pipe 1
Write the expression for the total head loss.
Write the expression for the pump head.
Here, the gravitational acceleration is
Write the expression for the pumping power.
Calculation:
Refer to table A-7 "properties of liquid" to obtain the loss coefficient for the pipe as
Substitute
Substitute
Substitute
Substitute
Refer to chart "the moody's chart" to obtain the friction factor at Reynolds number
Substitute
Substitute
Substitute
Substitute
Substitute
Refer to chart "the moody's chart" to obtain the friction factor at Reynolds number
Substitute
Substitute
Substitute
Substitute
Conclusion:
The required pumping head is
The pumping power required to maintain the flow is
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Chapter 8 Solutions
Fluid Mechanics: Fundamentals and Applications
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