Homework Help is Here – Start Your Trial Now!
Engineering
Mechanical Engineering
The cold storage room is maintained at T; = -70 °C by two stage vapor-compression refrigeration unit. In the low temperature cycle, R170 (ethane) is used as the working fluid. In the high temperature cycle, R134a is used as the working fluid. After selecting reasonable pressures for all heat exchangers, calculate evaporator capacity, COP of the system, and compressor powers. Show refrigeration cycles on P-h diagrams uploaded with the midterm exam question sheet. Draw the T-s diagrams of R134a and R170 cycles as well. Draw schematic of refrigeration system with its components. Notes UL 1) Isentropic efficiency of compressors are 0.75. 2) Refrigerants leave the condensers as saturated liquid and exit from the evaporators as saturated vapor. 3) When determining the cooling requirement, only the wall conduction load will be taken into account. (consider 5 walls, neglect heat loss through the floor) 4) The inner and outer walls are normally covered with steel sheets, but their conduction resistance can be neglected due to high heat conductivity constant k of steel. See the Lecture Note titled "Refrigeration" regarding two stage vapor-compression refrigeration cycles. Cold Storage 5 cm thick polyurethane foam insulation material is used for all storage walls. Kurethane = 0.035 W/m.°C %3D 2m T; = -70 °C h, = 10 W/m?.°C T, = 25 °C h, = 10 W/m?.°C 1 m 1 m Heat loss through the floor is neglected.

The cold storage room is maintained at T; = -70 °C by two stage vapor-compression refrigeration unit. In the low temperature cycle, R170 (ethane) is used as the working fluid. In the high temperature cycle, R134a is used as the working fluid. After selecting reasonable pressures for all heat exchangers, calculate evaporator capacity, COP of the system, and compressor powers. Show refrigeration cycles on P-h diagrams uploaded with the midterm exam question sheet. Draw the T-s diagrams of R134a and R170 cycles as well. Draw schematic of refrigeration system with its components. Notes UL 1) Isentropic efficiency of compressors are 0.75. 2) Refrigerants leave the condensers as saturated liquid and exit from the evaporators as saturated vapor. 3) When determining the cooling requirement, only the wall conduction load will be taken into account. (consider 5 walls, neglect heat loss through the floor) 4) The inner and outer walls are normally covered with steel sheets, but their conduction resistance can be neglected due to high heat conductivity constant k of steel. See the Lecture Note titled "Refrigeration" regarding two stage vapor-compression refrigeration cycles. Cold Storage 5 cm thick polyurethane foam insulation material is used for all storage walls. Kurethane = 0.035 W/m.°C %3D 2m T; = -70 °C h, = 10 W/m?.°C T, = 25 °C h, = 10 W/m?.°C 1 m 1 m Heat loss through the floor is neglected.

Elements Of Electromagnetics
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
See similar textbooks
icon
Related questions
Question
The cold storage room is maintained at T; = -70 °C by two stage vapor-compression refrigeration unit. In the low temperature cycle, R170 (ethane) is used as the working fluid. In the high temperature cycle, R134a is used as the working fluid. After selecting reasonable pressures for all heat exchangers, calculate evaporator capacity, COP of the system, and compressor powers. Show refrigeration cycles on P-h diagrams uploaded with the midterm exam question sheet. Draw the T-s diagrams of R134a and R170 cycles as well. Draw schematic of refrigeration system with its components. Notes UL 1) Isentropic efficiency of compressors are 0.75. 2) Refrigerants leave the condensers as saturated liquid and exit from the evaporators as saturated vapor. 3) When determining the cooling requirement, only the wall conduction load will be taken into account. (consider 5 walls, neglect heat loss through the floor) 4) The inner and outer walls are normally covered with steel sheets, but their conduction resistance can be neglected due to high heat conductivity constant k of steel. See the Lecture Note titled "Refrigeration" regarding two stage vapor-compression refrigeration cycles. Cold Storage 5 cm thick polyurethane foam insulation material is used for all storage walls. Kurethane = 0.035 W/m.°C %3D 2m T; = -70 °C h, = 10 W/m?.°C T, = 25 °C h, = 10 W/m?.°C 1 m 1 m Heat loss through the floor is neglected.
Transcribed Image Text:The cold storage room is maintained at T; = -70 °C by two stage vapor-compression refrigeration unit. In the low temperature cycle, R170 (ethane) is used as the working fluid. In the high temperature cycle, R134a is used as the working fluid. After selecting reasonable pressures for all heat exchangers, calculate evaporator capacity, COP of the system, and compressor powers. Show refrigeration cycles on P-h diagrams uploaded with the midterm exam question sheet. Draw the T-s diagrams of R134a and R170 cycles as well. Draw schematic of refrigeration system with its components. Notes UL 1) Isentropic efficiency of compressors are 0.75. 2) Refrigerants leave the condensers as saturated liquid and exit from the evaporators as saturated vapor. 3) When determining the cooling requirement, only the wall conduction load will be taken into account. (consider 5 walls, neglect heat loss through the floor) 4) The inner and outer walls are normally covered with steel sheets, but their conduction resistance can be neglected due to high heat conductivity constant k of steel. See the Lecture Note titled "Refrigeration" regarding two stage vapor-compression refrigeration cycles. Cold Storage 5 cm thick polyurethane foam insulation material is used for all storage walls. Kurethane = 0.035 W/m.°C %3D 2m T; = -70 °C h, = 10 W/m?.°C T, = 25 °C h, = 10 W/m?.°C 1 m 1 m Heat loss through the floor is neglected.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 4 steps with 6 images

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Knowledge Booster
Refrigeration and Air Conditioning
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Elements Of Electromagnetics
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY
SEE MORE TEXTBOOKS