# Recent questions tagged refrigeration-and-air-conditioning

Consider an ideal vapor compression refrigeration cycle. If the throttling process is replaced by an isentropic expansion process, keeping all the other processes unchanged, which one of the following statements is true for the modified cycle? Coefficient of performance is ... of performance is the same as that of the original cycle Refrigerating effect is lower than that of the original cycle
A refrigerator uses $R-134a$ as its refrigerant and operates on an ideal vapour-compression refrigeration cycle between $0.14 \: MPa$ and $0.8 \: MPa$.if the mass flow rate of refrigerant is $0.05 \: kg/s$,the rate of heat rejection to the environment is_______$kW$ ... $\text{At } P=0.8 \: MPa, \: h=93.42 \: kJ/kg, \: \text{ (saturated liquid) }$
The heat removal rate from a refrigerated space and the power input to the compressor are $7.2$ $kW$ and $1.8$ $kW$, respectively. The coefficient of performance (COP) of the refrigerator is ______
Refrigerant vapor enters into the compressor of a standard vapor compression cycle at −$10^\circ C \:(h = 402 \: kJ/kg)$ and leaves the compressor at $50^\circ C \: (h = 432 \: kJ/kg)$. It leaves the condenser at $30^\circ C \: (h = 237 \: kJ/kg)$. The COP of the cycle is ________
A reversed Carnot cycle refrigerator maintains a temperature of −$5^{\circ}$ $C$. The ambient air temperature is $35^{\circ}$ $C$. The heat gained by the refrigerator at a continuous rate is $2.5$ kJ/s. The power (in watt) required to pump this heat out continuously is _______
A heat pump with refrigerant $R22$ is used for space heating between temperature limits of $−20^\circ C$ and $25^ \circ C$. The heat required is $200 MJ/h$. Assume specific heat of vapour at the time of discharge as $0.98 kJ/kg.K$. Other relevant properties are given below. The enthalpy (in $kJ/kg$) of the refrigerant at isentropic compressor discharge is _______
Which one of the following is a CFC refrigerant? $R744$ $R290$ $R502$ $R718$