Heating Ventilating and Air Conditioning: Analysis and Design
6th Edition
ISBN: 9780471470151
Author: Faye C. McQuiston, Jeffrey D. Spitler, Jerald D. Parker
Publisher: Wiley, John & Sons, Incorporated
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Chapter 5, Problem 5.14P
Refer to Problem 5-13, and estimate the unit thermal resistance assuming the air space has one bright aluminum foil surface.
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The Diamond Ring Solution. The processing chip on the computer that controls the navigation equipment on your spacecraft is
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(a) Find the refrigeration capacity if no insulation is used for the walls and ceiling.
(b) Select insulation(s) for the wall and ceiling to reduce the refrigeration capacity.
Evaluate the thickness required for the insulation you selected to reduce the
refrigeration load by approximately 30%.
(c) Add a 1m x 1m window glass to the room. Use the data collected from previous parts.
Assume the internal surroundings surfaces (e.g., walls and ceilings) have the same
temperature as the inside temperature, and the external surroundings (landscape,
buildings, etc.) are also at the same temperature as the outside temperature. Assume
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same as the walls and the air. If the glass has an emissivity of 0.9, calculate the rate of
heat loss through the glass. Assume steady-state conditions, negligible temperature
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There are 2 options to be considered to form the insulation layer between the refractory
brick and air space, which are fiberglass and firebrick. Calculate the minimum thickness
required for the both fiberglass and firebrick. Which option do you recommend?
Comment. State the assumption in your calculation.
Based on your recommendation, calculate the temperature at each interface throughout the
wall and draw a temperature variation diagram from inside wall surface to outside wall
surface.
* Refractory
brick
Fiberglass or
firebrick?
0.5" Plaster
Heat
Ambient
source
Air spáce
4 Concrete block
Figure 2
Chapter 5 Solutions
Heating Ventilating and Air Conditioning: Analysis and Design
Ch. 5 - Determine the thermal conductivity of 4 in. (100...Ch. 5 - Compute the unit conductance C for 512 in. (140...Ch. 5 - Compute the unit thermal resistance and the...Ch. 5 - What is the unit thermal resistance for an inside...Ch. 5 - Compute the thermal resistance per unit length for...Ch. 5 - Assuming that the blocks are not filled, compute...Ch. 5 - The partition of Problem 5-4 has still air on one...Ch. 5 - The pipe of Problem has water flowing inside with...Ch. 5 - Compute the overall thermal resistance of a wall...Ch. 5 - Compute the overall heat-transfer coefficient for...
Ch. 5 - Estimate what fraction of the heat transfer for a...Ch. 5 - Make a table similar to Table 5-4a showing...Ch. 5 - Estimate the unit thermal resistance for a...Ch. 5 - Refer to Problem 5-13, and estimate the unit...Ch. 5 - A ceiling space is formed by a large flat roof and...Ch. 5 - A wall is 20 ft (6.1 m) wide and 8 ft (2.4 m) high...Ch. 5 - Estimate the heat-transfer rate per square foot...Ch. 5 - A wall exactly like the one described in Table...Ch. 5 - Prob. 5.19PCh. 5 - Compute the overall heat-transfer coefficient for...Ch. 5 - Compute the overall heat transfer for a single...Ch. 5 - Determine the overall heattransfer coefficient for...Ch. 5 - A basement is 2020ft(66m) and 7 ft (2.13 m) below...Ch. 5 - Estimate the overall heat-transfer coefficient for...Ch. 5 - Rework Problem 5-23 assuming that the walls are...Ch. 5 - A heated building is built on a concrete slab with...Ch. 5 - A basement wall extends 6 ft (1.8 m) below grade...Ch. 5 - A 2440ft(7.312.2m) building has a full basement...Ch. 5 - The floor of the basement described in Problem...Ch. 5 - Assume that the ground temperature tg is 40 F (10...Ch. 5 - Use the temperatures given in Problem 5-30 and...Ch. 5 - A small office building is constructed with a...Ch. 5 - A 100 ft length of buried, uninsulated steel pipe...Ch. 5 - Estimate the heat loss from 100 m of buried...Ch. 5 - A large beverage cooler resembles a small building...Ch. 5 - Consider the wall section shown in Fig. 5-10. (a)...Ch. 5 - A building has floor plan dimensions of 3060ft....Ch. 5 - Compute the temperature of the metal roof deck of...Ch. 5 - Consider the wall section shown in Fig. -4a,...Ch. 5 - Consider the knee space shown in Fig. 5-11. The...Ch. 5 - Estimate the temperature in an unheated basement...
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