1. What are the motivations for developing hermetic compressors? 2. Why is it impractical to apply the Reversed Carnot Cycle in an actual vapor compression refrigeration system? Explain. 3. What type of compressor and what type of refrigeration system are applied in central air conditioning of high rise buildings? Explain. 4. Discuss the usefulness of the p-h diagram in analyzing a vapor compression refrigeration cycle.

1. What are the motivations for developing hermetic compressors? 2. Why is it impractical to apply the Reversed Carnot Cycle in an actual vapor compression refrigeration system? Explain. 3. What type of compressor and what type of refrigeration system are applied in central air conditioning of high rise buildings? Explain. 4. Discuss the usefulness of the p-h diagram in analyzing a vapor compression refrigeration cycle.

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

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

See similar textbooks

Similar questions

What are higher-efficiency refrigerant blends that can be used as long-term replacements for R-22 in residential and light-commercial air-conditioning applications?
Why is truck refrigeration designed to provide low- and medium-temperature refrigeration?
Define flash gas, and explain how it applies to the net refrigeration effect of the refrigeration cycle.
What are the approximate temperature ranges tor low-, medium-, and high-temperature refrigeration applications?
When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be higher in temperature than the entering air temperature.
The values of a vapor compression refrigeration cycle were given below. Calculate the values ofrefrigerant flow rate, refrigeration capacity, and the COP of the system.T1= Evaporator water outlet = 10 °CT2= Evaporator water inlet = 16 °CT3= Condenser water inlet = 16 °CT4= Condenser water outlet = 22°CCooling water flow rate = 1.5 L/minHeating water flow rate = 1.5 L/minEnthalpy of R134a in evaporator outlet = 305 kj/kg,Enthalpy of R134a in evaporator inlet =115 kj/kgEnthalpy of R134a in condenser inlet =327 kj/kg
Problem 1 (Using thermodynamic tables)A large refrigeration plant is to be maintained at -12 C. It requires refrigeration at a rate of 120 kW.The condenser of the plant is to be cooled by liquid water, which experiences a temperature rise of 10 C as it flows over the coils of the condenser. Assuming the plant operates on the ideal vapor-compression cycle using refrigerant- 134a between the pressure limits of 100 and 700 kPa, determine (a) the mass flow rate of the refrigerant, (b) the power input to the compressor, and (c) the mass flow rate of the cooling water
Why is the reversed Carnot cycle executed within the saturation dome not a realistic model for refrigeration cycles?
1. Explain how the expansion valve in the refrigeration system works?2. Explain the mechanism of the capillary tube that is usedas an expansion valve?3. Describe the cascade refrigeration system?4 .Prove whether the cascade refrigeration system can increase the refrigeration COP? Materi:thermodynamics
A R-134A vapor refrigeration cycle cycle operates at an evaporator temperature of 20 Celsius and a condensing temperature of 35 Celsius. Determine the coefficient performance for. Ideal saturation cycle. Wet compression with saturated vapor leaving the compressor . Suction to the compressor is superheated by 7 degrees Celsius. Using this table https://www.docdroid.net/VkxK8WH/refrigerant-134a-pdf
The COP of vapor-compression refrigeration cycles improves when the refrigerant is subcooled before it enters the throttling valve. Can the refrigerant be subcooled indefinitely to maximize this effect, or is there a lower limit? Explain.
A standard vapor compression system produces 70.4 kW of refrigeration using R-12as a refrigerant while operating between a condenser temperature of 42 °C and anevaporator temperature of –25 °C.2.1 Draw the p-h diagram of the cycle. 2.2 Determine:(a) the refrigerating effect in kJ/kg, (b) the circulating rate in kg/s, (c) the power supplied, (d) the COP, (e) the heat rejected in kW, and(f) the volume flow rate in m3/s.