Psychrometry is the study of the properties of mixtures of airandwatervapour. Atmospheric air is a mixture of many gases pluswatervapourand a number of pollutants. The temperature in a 30-person workplace should be kept at 22C DB and 55 percent RH. The temperature outside is 36C DB and 27C WB. Solar heat gain = 8,500W; Sensible heat gain per occupant = 83 W; Latent heat gain per person = 100W; Lighting load = 2,500W; Sensible heat load from other sources = 12,000W; and Infiltration load = 15 m3/min are the different loads in the office. Calculate the answers based on 40 percent fresh air and 60 percent recirculated air going through the evaporator coil and a by-pass factor of 0.12: Determine the Air - conditioning Plant's Performance in Tons of Refrigeration.

Psychrometry is the study of the properties of mixtures of airandwatervapour. Atmospheric air is a mixture of many gases pluswatervapourand a number of pollutants. The temperature in a 30-person workplace should be kept at 22C DB and 55 percent RH. The temperature outside is 36C DB and 27C WB. Solar heat gain = 8,500W; Sensible heat gain per occupant = 83 W; Latent heat gain per person = 100W; Lighting load = 2,500W; Sensible heat load from other sources = 12,000W; and Infiltration load = 15 m3/min are the different loads in the office. Calculate the answers based on 40 percent fresh air and 60 percent recirculated air going through the evaporator coil and a by-pass factor of 0.12: Determine the Air - conditioning Plant's Performance in Tons of Refrigeration.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 8RQ: Frost accumulates on the evaporators of forced-draft refrigerators because A. they are generally...

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An engineer has been given the following data on a conditioned room: Sensible heat gain 30 kW Latent heat gain 15 kW Supply air 18°C Outdoor air 35°C DB and 24°C WB Desired room condition 27°C DB and 50% RH For ventilation, 15% is outdoor air, the balance of air requirement being recirculated from room conditioned with some portion being by-passed around the cooling coil. There is no reheater, the desired room state is attained by the by-passing of air. It is found that the apparatus DP temperature of coil is 10°C. Find the: a. tons of refrigeration; and b. mass flow rate of the time by-passed air.
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