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Using Fig. 4-1, draw a conclusion about the comfort of a mixed group of men and women in typical seasonal clothing, with sedentary activity for the following cases:
a. Summer, operative temperature 77 F, wb 64 F
b. Winter, operative temperature. 77 F, wb 64 F
c. Summer, operative temperature 75 F, dp 50 F
d. Winter, operative temperature 73 F, dp 34 F
(a)
The comfort of mixed group of men and women in typical seasonal clothing.
Answer to Problem 4.1P
According to given condition, the group will feel comfortable.
Explanation of Solution
Given:
The operating temperature of summer is
The wet bulb temperature of summer is
Calculation:
From fig4-1,
According to ASHRAE standard, the acceptable range of operating temperature is
(b)
The comfort of mixed group of men and women in typical seasonal clothing.
Answer to Problem 4.1P
According to given condition, the group will not feel comfortable.
Explanation of Solution
Given:
The operative temperature of winter is
The wet bulb temperature of winter is
Calculation:
From fig4-1,
According to ASHRAE standard, the acceptable range of operating temperature is
(c)
The comfort of mixed group of men and women in typical seasonal clothing.
Answer to Problem 4.1P
According to given condition, the group will feel comfortable
Explanation of Solution
Given:
The operative temperature of summer is
The dew temperature of summer is
Calculation:
From fig4-1,
According to ASHRAE standard, the acceptable range of operating temperature is
(d)
The comfort of mixed group of men and women in typical seasonal clothing.
Answer to Problem 4.1P
According to given condition, the group will feel uncomfortable.
Explanation of Solution
Given:
The operative temperature of winter is
The dew temperature of winter is
Calculation:
From fig4-1,
According to ASHRAE standard, the acceptable range of operating temperature is
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Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning