10-Intro, fluid mech
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Significant Learning Outcom ...
C H A P T E R
10
Flow in
Conduits
SIGIFICAT LEARIG OUTCOMES
The Alaskan pipeline, a significant accomplishment of the engineering profession,
transports oil 1286 km across the state of Alaska. The pipe diameter is 1.2 m, and the
44 pumps are used to drive the flow. This chapter presents information for designing
systems involving pipes, pumps, and turbines.
Conceptual Knowledge
·
Describe laminar flow, turbulent flow, developing flow, and fully developed flow in a
conduit.
·
Describe how to characterize total head loss by using component and pipe head loss.
·
List the steps used to derive the (a) Darcy-Weisbach equation and (b)Poiseuille flow
solution.
·
Describe the main features of the Moody diagram.
Procedural Knowledge
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Significant Learning Outcom ...
·
Classify flow as (a) laminar or turbulent and (b) developing or fully developed.
·
Using equations or the Moody diagram, find values of the friction factor
f
.
·
Calculate pipe head loss, component head loss, and total head loss.
Typical Applications
·
For flow in a pipe, find the pressure drop or head loss.
·
For a specified system, find the flow rate.
·
For a specified flow rate and pressure drop, determine the size of pipe required.
·
For a system with a pump, find the pump specifications (power, head, flow rate).
·
For a specified elevation change and flow rate, find the power that can be produced by a
turbine.
The fundamentals of the energy equation were presented in Chapter 7, and the fundamentals of shear
stress, velocity profiles, and boundary layer in Chapter 9. This chapter combines these ideas to
describe flow in conduits. A
conduit
is any pipe, tube, or duct that is completely filled with a flowing
fluid. Examples include a pipeline transporting liquefied natural gas, a microchannel transporting
hydrogen in a fuel cell, and a duct transporting air for heating of a building. A pipe that is partially
filled with a flowing fluid, for example a drainage pipe, is classified as an open-channel flow and will
be analyzed in Chapter 15.
The main goal of this chapter is to describe how to predict head loss. Predicting head loss involves
classifying flow as laminar or turbulent and then using equations to calculate head losses in pipes and
components. This chapter also describes how to use data from a pump manufacturer to select the
right size of pump for a given application and how to model a network of pipes.
Copyright ¨ 2009 John Wiley & Sons, Inc. All rights reserved.
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