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 4, Problem 4.32P
A classroom with a capacity of 225 people is isolated from the outdoors except for the incoming ventilation air. The cooling load is 123,000 Btu/hr (37 kW) with a sensible heat factor of 0.7. The minimum 15 cfm/person (7.5 L/s per person) is assumed adequate. (a) Compute the required amount of ventilation air (supply air) on the basis of the cooling load, assuming that the space dry bulb is 75 F (24 C) and 50 percent relative humidity and that the air is supplied at 90 percent relative humidity (RH). (b) What is the minimum air supply rate based on indoor air quality requirements? (c) Compare parts (a) and (b) and discuss the best course of action.
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Gases after combustion are discharged from a flue in a facility to the atmosphere at a temperature of 250 °C and a flow rate of 25000 m3/h. It is desired to benefit from the heat of this waste gas in heating. There is a site with 40 residences, each with a heating load of approximately 8 kW, located 3 km from the facility.1- Determine the substation capacity to be used, taking into account the hot water requirement for each house on the site.2- Determine the substation inlet/outlet temperature and the heat exchanger water inlet/outlet temperatures. The temperature of the water leaving the heat exchanger is required not to exceed 95 ° C. The pipeline between the facility and the site is underground pipeline. Determine the required data by considering the region where the facility is located, calculate the heat losses in the line and find the required insulation thickness.3- Calculate the total capacity including losses and determine the required exchanger dimensions.
insulation…
Gases after combustion are discharged from a flue in a facility to the atmosphere at a temperature of 250 °C and a flow rate of 25000 m3/h. It is desired to benefit from the heat of this waste gas in heating. There is a site with 40 residences, each with a heating load of approximately 8 kW, located 3 km from the facility.1- Determine the substation capacity to be used, taking into account the hot water requirement for each house on the site.2- Determine the substation inlet/outlet temperature and the heat exchanger water inlet/outlet temperatures. The temperature of the water leaving the heat exchanger is required not to exceed 95 ° C. The pipeline between the facility and the site is underground pipeline. Determine the required data by considering the region where the facility is located, calculate the heat losses in the line and find the required insulation thickness.3- Calculate the total capacity including losses and determine the required exchanger dimensions.
Gases after combustion are discharged from a flue in a facility to the atmosphere at a temperature of250 °C and a flow rate of 25000 m3/h. It is desired to benefit from the heat of this waste gas in heating.There is a site with 40 residences, each with a heating load of approximately 8 kW, located 3 km fromthe facility.1- Determine the substation capacity to be used, taking into account the hot water requirement foreach house on the site.2- Determine the substation inlet/outlet temperature and the heat exchanger water inlet/outlettemperatures. The temperature of the water leaving the heat exchanger is required not to exceed 95° C. The pipeline between the facility and the site is underground pipeline. Determine the requireddata by considering the region where the facility is located, calculate the heat losses in the line andfind the required insulation thickness.3- Calculate the total capacity including losses and determine the required exchanger dimensions.
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Chapter 4 Solutions
Heating Ventilating and Air Conditioning: Analysis and Design
Ch. 4 - Using Fig. 4-1, draw a conclusion about the...Ch. 4 - Using Fig. 4-1, draw a conclusion about the...Ch. 4 - Select comfortable summer design conditions (dry...Ch. 4 - It is desired to use a space as a large classroom...Ch. 4 - An indoor tennis facility finds that it has...Ch. 4 - Work Problem 4-5 for an average air speed at court...Ch. 4 - In an occupied space the mean air velocity is...Ch. 4 - An occupied space is being held at 76 F (24 C) and...Ch. 4 - What do you think is the best thermostat setting...Ch. 4 - With the air conditioning running and the...
Ch. 4 - Discuss how an emergency government mandate to set...Ch. 4 - In the heating seasons the heat loss from a...Ch. 4 - Air motion can be good or bad, depending on the...Ch. 4 - To save energy in large, chilled water systems,...Ch. 4 - Overhead fans (Casablanca fans) are often reversed...Ch. 4 - A school classroom is designed for 30 people. (a)...Ch. 4 - Carbon dioxide is being generated in an occupied...Ch. 4 - Each person in a room is assumed to be producing...Ch. 4 - An air-handling system must handle 2000 cfm with a...Ch. 4 - Prob. 4.20PCh. 4 - How many filter modules will be required using the...Ch. 4 - Work Problem 4-21 assuming that the filter is a...Ch. 4 - The M-200, 0.60.60.2 filters of Table 4-3 are to...Ch. 4 - Investigate the feasibility of using 100 percent...Ch. 4 - Work Problem 4-24 but replace the 100 percent...Ch. 4 - Using M-15 filter media and the requirement of 60...Ch. 4 - A filter system is available that will filter out...Ch. 4 - A maximum of 10 smokers are anticipated in a smong...Ch. 4 - Solve Ex. 4-4 assuming that the filter is in...Ch. 4 - Solve Problem 4-28 assuming that the filter is in...Ch. 4 - Fora 3000-ft3 combination and exercise operation,...Ch. 4 - A classroom with a capacity of 225 people is...
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