3.23: An ideal refrigeration cycle operates with R134a as the working fluid. The temperature of refrigerant in the condenser and evaporator are 40°c and -20°c respectively. The mass flow rate of refrigerant is 0.1 kg/s. Determine the cooling capacity and cop of the plant. Take enthalpy of refrigerant vapour at the end of compression as 276 kJ/kg. 40°C -20°C/ 3

3.23: An ideal refrigeration cycle operates with R134a as the working fluid. The temperature of refrigerant in the condenser and evaporator are 40°c and -20°c respectively. The mass flow rate of refrigerant is 0.1 kg/s. Determine the cooling capacity and cop of the plant. Take enthalpy of refrigerant vapour at the end of compression as 276 kJ/kg. 40°C -20°C/ 3

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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The evaporator and condenser is isobaric with a net heat transfer 250 W in a vapor-compression refrigeration cycle. The cycle operates with R-134a working fluid at a steady state. The compressor's isentropic efficiency is at 60% with a high pressure of 16 bar and low pressure of 1 bar during the cycle. Solve for the mass flow rate, coefficient of performance, and draw the T-s diagram.
Q.13 A vapour compression refrigeration system using refrigerant F-12 is employed to produce 8640 kg of ice per day. The condensing and evaporating temperature of refrigcrant are 48°C and-20°C respectively. Saturated liquid leaves the condenser and saturated vapour leaves the evaporator. Compression is isentropic, water at 35°C is used to form the ice. The temperature of ice should be-8°C. Heat flow into the brine tank from surroundings may be taken as 10% of total heat absorbed from water to form ice. Determine the power required to drive the compressor. Take specific heat of ice 2.26 kJ/kg-K. Latent heat of ice = 335 kJ/kg. Specific heat of water = 4.2 kJ/kg-K. The following data may be used: %3D Temp. Pressure Enthalpy Entropy °C bar kJ/lg kJ/kg-K Liquid Vapour Liquid Vapour 48°C 11.64 82.83 205.83 0.2973 0.6802 -20 1.51 17.82 178.74 0.0731 0.7087 Specific heat of vapour 0.82 kJ/kg %3D
An ideal vapor compression cycle operates between the temperature limits of -5 °c and 30 °C and uses R134a as the refrigerant, which flows at a rate of 0.6 kg/s. The P-h- as well as T-s-diagrams that illustrate the refrigerating process is given in diagram, and respectively. Refigerant is compressed to the state in the compressor and heat is rejected in the condenser at constant for ideal Vapour compression cycle.
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8.
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