Refrigeration and Air Conditioning Technology (MindTap Course List)
8th Edition
ISBN: 9781305578296
Author: John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher: Cengage Learning
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Chapter 33, Problem 29RQ
Drain-down systems would best be used in which geographic area?
A. Colder climates
B. Warmer climates
C. Climates with very low humidity
D. Climates with very high humidity
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An aluminum rod of length L
=
1m has mass density p = 2700 kg and
Young's modulus E = 70 GPa. The rod is fixed at both ends. The exact
natural eigenfrequencies of the rod are wexact
E
=
√
ρ
for n=1,2,3,. . . .
1. What is the minimum number of linear elements necessary to
determine the fundamental frequency w₁ of the system? Discretize
the rod in that many elements of equal length, assemble the global
system of equations KU = w² MU, and find the fundamental
frequency w₁. Compute the relative error e₁ = (w1 - wexact) /w exact
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Chapter 33 Solutions
Refrigeration and Air Conditioning Technology (MindTap Course List)
Ch. 33 - A hydronic heating system uses ______to move heat...Ch. 33 - Describe a zone in a hydronic heating system.Ch. 33 - Name four sources of heat commonly used for...Ch. 33 - Give three reasons that air is detrimental to a...Ch. 33 - Explain the difference between a wet-base and a...Ch. 33 - Where is air vented from a hydronic heating...Ch. 33 - The "point of no pressure change" is located at...Ch. 33 - The purpose of a limit control in a boiler is to...Ch. 33 - The device that relieves the pressure in a boiler...Ch. 33 - Describe the function of a low-water cutoff.
Ch. 33 - The relief valve setting for a typical...Ch. 33 - Describe how an air cushion tank functions in a...Ch. 33 - True or False: City water does not contain air.Ch. 33 - State two ways that air can get into a hydronic...Ch. 33 - The most common type of pump used for hydronic...Ch. 33 - Another term for pump pressure is feet of _______.Ch. 33 - Two types of zone control valves are the _____and...Ch. 33 - Why must expansion be considered when sizing...Ch. 33 - How is expansion in hot water pipes handled?Ch. 33 - Sketch the following systems: one pipe, two-pipe...Ch. 33 - Describe the advantage of a two-pipe...Ch. 33 - The pressure differential bypass valve is most...Ch. 33 - What is the heat output, in Btu/h, of a terminal...Ch. 33 - In a primary-secondary pumping arrangement, the...Ch. 33 - The temperature of the water at the outlet of a...Ch. 33 - A tankless water-heating system gets its heat from...Ch. 33 - How much of the sun's energy actually reaches the...Ch. 33 - The varying intensity of the sun's energy that...Ch. 33 - Drain-down systems would best be used in which...Ch. 33 - Why are solar systems intended to be used as a...
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