Concept explainers
A horizontal pipe has an abrupt expansion from
The Downstream pressure and the error that would have occurred if Bernoulli’s equation had been used.
Answer to Problem 66P
The Downstream pressure is
Explanation of Solution
Given information:
The diameter of the smaller pipe that is pipe 1 is
The flow is assumed to be steady, fully developed and incompressible, and the kinetic energy correction factor for both inlet and outlet is equal.
Write the expression for the cross section flow area of pipe 1.
Here, the diameter of the smaller pipe is
Write the expression for the cross section flow area of pipe 2.
Here, the diameter of the bigger pipe is
Write the expression for the velocity of water using the conservation of mass flow.
Here, the cross section area of the smaller pipe is
Write the expression of the loss coefficient for sudden expansion.
Here, the cross section area of the smaller pipe is
Write the expression for the head loss.
Here, the loss coefficient for sudden expansion is
Write the expression for the energy equation for the horizontal expansion section in terms of heads excluding the wok devices.
Here, the pressure in the bigger section is
Write the expression for the Bernoulli’s equation for the horizontal pipe.
Here, the pressure in the bigger pipe is
Write the expression for finding the error in the Bernoulli’s equation.
Write the expression for finding the error percentage.
Calculation:
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Conclusion:
The Downstream pressure is
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Chapter 8 Solutions
FLUID MECHANICS:FUND.+APPL.(LL)>CUSTOM<
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