Carnot Refrigeration cycle & Bell Coleman Cycle | Quizizz

200 kg of ice at – 10C is placed in a bunker to cool some vegetables. 24 hours later the ice has melted into water at 5C. What is the average rate of cooling in kJ/hr and TR provided by the ice? Assume Specific heat of ice, c = 1.94 kJ/kg oC Specific heat of water, c = 4.1868 kJ/kg oC Latent heat of fusion of ice at 0C, L = 335 kJ/kg.

What is the coefficient of performance of the refrigerant system working on reversed Carnot cycle, having Q as heat absorbed by the air during isothermal expansion per kg of air and Q as heat rejected during isothermal compression per kg of air?

A bell coleman refrigeration cycle works between pressure limits of 1 bar and 5 bar. The adiabatic efficiency of compression is 85% and expansion is 90%. Find out the tonnage capacity when the air flow rate is 1 kg/sec. The ambient temperature is 27°C and refrigerator temperature is 0°C

In a refrigeration plant working on Bell Coleman cycle, air is compressed to 5 bar from 1 bar. Its initial temperature is 10°C. After compression, the air is cooled up to 20°C in a cooler before expanding back to a pressure of 1 bar. Determine the theoretical C. O.P. of the plant and net refrigerating effect. Take cp = 1.005 kJ /kg K and cv = 0.718 kJ/kg K

The Bell-Coleman refrigeration cycle uses _____ as refrigerant.

• CO

• Air

• Ammonia

• HO

What happens to the COP of a Carnot refrigerator in summer and in winter?

• The COP is more in winter

• The COP is more in summer

• The COP remains unaffected

• The COP fluctuates continuously during winter and summer

Bell-Coleman cycle is also known as_______

• Carnot cycle

• Rankine cycle

• Otto cycle

• Reversed Brayton or Joule’s cycle

In a figure shown, E is heat engine with efficiency of 40% and R is Refrigerator. Given that- Q + Q = 3Q, A heat engine having efficiency of 70% is used to drive a refrigerator having COP of 5. The heat absorbed from lower temperature reservoir by the refrigerator for each kJ of heat absorbed from higher temperature source of engine (in kJ) is-

• 0.71

• 7.1

• 0.04

• 3.5

Which one is not a limitation of the Carnot cycle with air or gas as refrigerant?

• Machine has to run at high and low speeds during adiabatic and isothermal process. Such variation of speed is not possible

• It is not possible to carry out isothermal heat transfer process in practice

• It has low efficiency when working between two fixed temperature limits

• Extreme pressure and large volume are developed

For a refrigerating system that works on Bell-Coleman cycle, which one of the following is not a process of the cycle?

• Constant pressure expansion process

• Isentropic compression process

• Constant pressure cooling process

• Isothermal expansion process