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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Textbook Question
Chapter 5, Problem 5.35P
A large beverage cooler resembles a small building and is to be maintained at about 35 F (2 C) and a low relative humidity. The walls and ceiling are well insulated and are finished on the inside with plywood. Assume that the outdoor temperature is generally higher than 35 F (2 C). In what direction will moisture tend to migrate? Where should the vapor retardant be located? Explain what might happen if the retardant is improperly located.
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Is it possible that during sensible cooling process the condition of air reaches a relative humidity of more than 100%.
Required information
Problem 14.095 - Evaporative Swamp Cooler
NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.
Air enters an evaporative cooler at 1 atm, 40°C, and 20 percent relative humidity at a rate of 7 m³/min, and it leaves with a
relative humidity of 90 percent. Use data from the psychrometric chart.
1 atm
40°C
20%
Air
Water
Mw
Humidifier
€ £2=90%
Problem 14.095.a - Evaporative Swamp Cooler
Determine the exit temperature of the air.
The exit temperature of the air is
°C.
Is it possible that during sensible cooling process the condition of air reaches a relative humidity of more than 100% or Is it possible that during sensible cooling process the condition of air reaches a relative humidity of 0%?
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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- ASHRAE standard 62.2 states that the minimum acceptable rate of airflow into and out of a room is 15cfm (cubic feet per minute). If air is supplied at 68°F with a relative humidity of 45%, how many gallons of water (minimum) must be added to a portable room humidifier before you go to sleep if you would like to maintain the room at 65% humidity for 7 hours?arrow_forwardRead carefully. Please solve ellaborately and include the untis in every step, and write your solutions clearly and readable if your solution is in written form, Your work will be appreaciated much. Thank You! Atmospheric air from the inside of an automobile enters the evaporator section of the air conditioner at 1 atm, 27 C and 50 percent relative humidity. The air returns to the automobile at 10 C and 90 percent relative humidity. The passenger compartment has a volume of 2 m3 and 5 air changes per minute are required to maintain the inside of the automobile at the desired comfort level. Sketch the psychrometric diagram for the atmospheric air flowing through the air conditioning process. Determine the dew point and wet bulb temperatures at the inlet to the evaporator section, in 8 C. Answer the required heat transfer rate from the atmospheric air to the evaporator fluid, in kW. Answer the rate of condensation of water vapor in the evaporator section, in kg/min. Answerarrow_forwardDuring very cold weather at a 5000 ft high (1500 m high) mountain site in Colorado, the interior sur- face of a single-glazed window can reach 40°F (4°C). If the room is at 68°F (20°C), what is the maximum relative humidity that can exist in the room without condensations occurring on the window?arrow_forward
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