Question

In a 10 kW cooling capacity refrigeration system operating on VCRS, the refrigerant enters the evaporator with an enthalpy of 80 kJ/kg and leaves with an enthalpy of 180 kJ/kg. The enthalpy of the refrigerant after compression is 220 kJ/kg. The rate of heat transfer at the condenser is

• A. 21 kW
• B. 7 kW
• C. 3.5 kW
• D. 14 kW

Answer 1

The correct option is D 14 kW



$10=\dot{m}(h_1-h_4)=\dot{m}\times (180-80)$

$\Rightarrow \dot{m}=0.1kg/s$

$Heatrejectedincondenser=h_2-h_3$

= 220 - 80 = 140 kJ/kg

$Rateofheattransfer=0.1\times 140=14kW$