7-115 Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.8-m-long t inside which the refrigerant is evaporating at -20°C. Air approaches the tube bank in the normal direction at 0°C and 1 atm with a m velocity of 5 m/s. The tubes are arranged in-line with longitudinal and transverse pitches of SL ST = 1.5 cm. There are 25 rows in t flow direction with 15 tubes in each row. Determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. Evaluate the air properties at an assumed mean temperature of -5°C and 1 atm. Is this a good assumption? 0.8 m Air 0°C 1 atm Sr= 1.5 cm 5 m/s

7-115 Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.8-m-long t inside which the refrigerant is evaporating at -20°C. Air approaches the tube bank in the normal direction at 0°C and 1 atm with a m velocity of 5 m/s. The tubes are arranged in-line with longitudinal and transverse pitches of SL ST = 1.5 cm. There are 25 rows in t flow direction with 15 tubes in each row. Determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. Evaluate the air properties at an assumed mean temperature of -5°C and 1 atm. Is this a good assumption? 0.8 m Air 0°C 1 atm Sr= 1.5 cm 5 m/s

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Radiation

Radiation can be described as the energy in the form of a particular matter or electromagnetic waves traveling in the air and can be in the form of light, sound, and heat. Radiation can be detected through special instruments like X-rays. The radiation from a cooler object is less intense as compared to the radiation from hot objects.

Question

7-115 Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.8-m-long tubes
inside which the refrigerant is evaporating at –20°C. Air approaches the tube bank in the normal direction at 0°C and 1 atm with a mean
velocity of 5 m/s. The tubes are arranged in-line with longitudinal and transverse pitches of SL = ST = 1.5 cm. There are 25 rows in the
%D
flow direction with 15 tubes in each row. Determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube
bank. Evaluate the air properties at an assumed mean temperature of -5°C and 1 atm. Is this a good assumption?
0.8 m
Air
0°C
1 atm
ST = 1.5 cm
5 m/s
0.8 cm
1.5 cm/
S, =
Refrigerant, –20°C
FIGURE P7–115

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