Fluid Mechanics: Fundamentals and Applications
4th Edition
ISBN: 9781259696534
Author: Yunus A. Cengel Dr., John M. Cimbala
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 8, Problem 131P
A house built on a riverside is to be cooled iii summer by utilizing the cool water of the river. A 20-m-long section of a circular stainless-steel duct of 20-cui diameter passes through the water, Air flows through the underwater section of the duct at 4 m/s at an average temperature of 1 5.C. For an overall fan efficiency of 62 percent, determine the fan power needed to overcome the flow resistance in this section of the duct.
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Chapter 8 Solutions
Fluid Mechanics: Fundamentals and Applications
Ch. 8 - How is the hydrodynamic entry length defined for...Ch. 8 - Why are liquids usually transported in circular...Ch. 8 - What is the physical significance of the Reynolds...Ch. 8 - Consider a person walking first in air and then in...Ch. 8 - Show that the Reynolds number for flow in a...Ch. 8 - Which fluid at room temperature requires a larger...Ch. 8 - What is the eneia1Iy accepted value of the...Ch. 8 - Consider the flow of air and wale in pipes of the...Ch. 8 - Consider laminar flow in a circular pipe. Is the...Ch. 8 - How does surface roughness affect the pressure...
Ch. 8 - What is hydraulic diameter? How is it defined?...Ch. 8 - Shown here is a cool picture of water being...Ch. 8 - What fluid property is responsible for the...Ch. 8 - In the fully developed region of flow in a...Ch. 8 - Someone claims that the volume flow rate in a...Ch. 8 - Someone claims that the average velocity in a...Ch. 8 - Someone claims that the shear stress at the center...Ch. 8 - Someone claims that in fully developed turbulent...Ch. 8 - How does the wall shear stress w , vary along the...Ch. 8 - How is the friction factor for flow in a pipe...Ch. 8 - Discuss whether fully developed pipe flow is one-,...Ch. 8 - Consider fully developed flow in a circular pipe...Ch. 8 - Consider fully developed laminar how in a...Ch. 8 - Explain why the friction factor is independent of...Ch. 8 - Consider laminar flow of air in a circular pipe...Ch. 8 - Consider fully developed laminar flow in a...Ch. 8 - How is head loss related to pressure loss? For a...Ch. 8 - What is turbulent viscosity? What caused it?Ch. 8 - What is the physical mechanism that causes the...Ch. 8 - The head toss for a certain circular pipe is given...Ch. 8 - The velocity profile for the fully developed...Ch. 8 - Water at 15°C (p = 999.1 kg/m3 and = 1.138 × 10-3...Ch. 8 - Water at 70F passes through...Ch. 8 - Heated air at 1 atm and 100F is to be transported...Ch. 8 - In fully developed laminar flow in a circular...Ch. 8 - The velocity profile in fully developed laminar...Ch. 8 - Repeat Prob. 8-36 for a pipe of inner radius 7 cm.Ch. 8 - Water at 10C (p = 999.7 kg/m3 and = 1.307 ×...Ch. 8 - Consider laminar flow of a fluid through a square...Ch. 8 - Repeat Prob. 8-39 for tribulent flow in smooth...Ch. 8 - Air enters a 10-m-long section of a rectangular...Ch. 8 - Consider an air solar collector that is 1 m wide...Ch. 8 - Oil with p = 876 kg/m3 and = 0.24 kg/m.s is...Ch. 8 - Glycenii at 40 C with p = l22 kg/m3 and = 0.27...Ch. 8 - Air at 1 atm and 60 F is flowing through a 1 ft ×...Ch. 8 - Oil with a density of 850 kg/m3 and kinematic...Ch. 8 - In an air heating system, heated air at 40 C and...Ch. 8 - Glycerin at 40 C with p = 1252 kg/m3 and = 0.27...Ch. 8 - Liquid ammonia at 20 C is flowing through a...Ch. 8 - Consider the fully developed flow of glycerin at...Ch. 8 - The velocity profile for a steady laminar flow in...Ch. 8 - The generalized Bernoulli equation for unsteady...Ch. 8 - What is minor loss in pipe flow? How is the minor...Ch. 8 - Define equivalent length for minor loss in pipe...Ch. 8 - The effect of rounding of a pipe inlet on the loss...Ch. 8 - The effect of rounding of a pipe exit on the loss...Ch. 8 - Which has a greater minor loss coefficient during...Ch. 8 - A piping system involves sharp turns, and thus...Ch. 8 - During a retrofitting project of a fluid flow...Ch. 8 - A horizontal pipe has an abrupt expansion from...Ch. 8 - Consider flow from a water reservoir through a...Ch. 8 - Repeat Prob. 8-62 for a slightly rounded entrance...Ch. 8 - Water is to be withdrawn from an 8-m-high water...Ch. 8 - A piping system equipped with a pump is operating...Ch. 8 - Water is pumped from a large lower reservoir to a...Ch. 8 - For a piping system, define the system curve, the...Ch. 8 - Prob. 68CPCh. 8 - Consider two identical 2-m-high open tanks tilled...Ch. 8 - A piping system involves two pipes of different...Ch. 8 - A piping system involves two pipes of different...Ch. 8 - A piping system involves two pipes of identical...Ch. 8 - Water at 15 C is drained from a large reservoir...Ch. 8 - Prob. 74PCh. 8 - The water needs of a small farm are to be met by...Ch. 8 - Prob. 76EPCh. 8 - A 2.4-m-diameter tank is initially filled with...Ch. 8 - A 3-m-diameter tank is initially filled with water...Ch. 8 - Reconsider Prob. 8-78. In order to drain the tank...Ch. 8 - Gasoline (p = 680 kg/m3 and v = 4.29 × 10-7 m2/s)...Ch. 8 - Prob. 81EPCh. 8 - Oil at 20 C is flowing through a vertical glass...Ch. 8 - Prob. 83PCh. 8 - A 4-in-high cylindrical tank having a...Ch. 8 - A fanner is to pump water at 70 F from a river to...Ch. 8 - A water tank tilled with solar-heated vater at 4OC...Ch. 8 - Two water reservoirs A and B are connected to each...Ch. 8 - Prob. 89PCh. 8 - A certain pail of cast iron piping of a water...Ch. 8 - Repeat Prob. 8-91 assuming pipe A has a...Ch. 8 - Prob. 93PCh. 8 - Repeat Prob. 8-93 for cast lion pipes of the same...Ch. 8 - Water is transported by gravity through a...Ch. 8 - Water to a residential area is transported at a...Ch. 8 - In large buildings, hot water in a water tank is...Ch. 8 - Prob. 99PCh. 8 - Two pipes of identical length and material are...Ch. 8 - What are the primary considerations when selecting...Ch. 8 - What is the difference between laser Doppler...Ch. 8 - Prob. 103CPCh. 8 - Prob. 104CPCh. 8 - Explain how flow rate is measured with...Ch. 8 - Prob. 106CPCh. 8 - Prob. 107CPCh. 8 - Prob. 108CPCh. 8 - A 15-L kerosene tank (p = 820 kg/m3) is filled...Ch. 8 - Prob. 110PCh. 8 - Prob. 111PCh. 8 - Prob. 112PCh. 8 - Prob. 113PCh. 8 - Prob. 114EPCh. 8 - Prob. 115EPCh. 8 - Prob. 116PCh. 8 - A Venturi meter equipped with a differential...Ch. 8 - Prob. 119PCh. 8 - Prob. 120PCh. 8 - Prob. 121PCh. 8 - Prob. 122EPCh. 8 - Prob. 123PCh. 8 - The flow rate of water at 20°C (p = 998 kg/m3 and ...Ch. 8 - Prob. 125PCh. 8 - Prob. 126PCh. 8 - Prob. 127PCh. 8 - The conical container with a thin horizontal tube...Ch. 8 - Prob. 129PCh. 8 - The compressed air requirements of a manufacturing...Ch. 8 - A house built on a riverside is to be cooled iii...Ch. 8 - The velocity profile in fully developed lamina,...Ch. 8 - Prob. 133PCh. 8 - Two pipes of identical diameter and material are...Ch. 8 - Prob. 135PCh. 8 - Shell-and-tube heat exchangers with hundred of...Ch. 8 - Water at 15 C is to be dischaged froiti a...Ch. 8 - Consider flow front a reservoir through a...Ch. 8 - A pipelme ihat Eransports oil ai 4OC at a iate of...Ch. 8 - Repeat Prob. 8-140 for hot-water flow of a...Ch. 8 - Prob. 142PCh. 8 - Prob. 145EPCh. 8 - Prob. 146EPCh. 8 - In a hydroelectric power plant. water at 20°C is...Ch. 8 - Prob. 148PCh. 8 - Prob. 152PCh. 8 - The water at 20 C in a l0-m-diameter, 2-m-high...Ch. 8 - Prob. 155PCh. 8 - Find the total volume flow rate leaving a tank...Ch. 8 - Prob. 158PCh. 8 - Water is siphoned from a reservoir open to the...Ch. 8 - It is a well-known fact that Roman aqueduct...Ch. 8 - In a piping system, what is used to control the...Ch. 8 - Prob. 163PCh. 8 - Prob. 164PCh. 8 - Prob. 165PCh. 8 - Consider laminar flow of water in a...Ch. 8 - Water at 10 C flows in a 1.2-cm-diameter pipe at a...Ch. 8 - Engine oil at 20 C flows in a 15-cm-diamcter pipe...Ch. 8 - Prob. 169PCh. 8 - Watet flows in a I 5-cm-diameter pipe a, a...Ch. 8 - The pressure drop for a given flow is determined...Ch. 8 - Prob. 172PCh. 8 - Air at 1 atm and 25 C flows in a 4-cm-diameter...Ch. 8 - Hot combustion 8ases approximated as air at I atm...Ch. 8 - Air at 1 aim and 40 C flows in a 8-cm-diameter...Ch. 8 - The valve in a piping system cause a 3.1 in head...Ch. 8 - A water flow system involves a 180 return bend...Ch. 8 - Air flows in an 8-cm-diameter, 33-m-long pipe at a...Ch. 8 - Consider a pipe that branches out into two...Ch. 8 - Prob. 182PCh. 8 - Prob. 183PCh. 8 - Prob. 184PCh. 8 - Prob. 185PCh. 8 - Prob. 186PCh. 8 - Design an experiment to measure the viscosity of...Ch. 8 - During a camping trip you notice that water is...
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