A plant using R134a evaporates at 2°C and condenses at 36°C with 4K of
superheat at the evaporator outlet and 4K of sub-cooling at the outlet
from the condenser. The duty is 352 kW of refrigeration. Assuming
isentropic compression and ignoring pressure drops in the piping,
evaporator and condenser, calculate the following:
the dryness fraction at entry to the evaporator,
the refrigerating effect,
the mass flow rate of refrigerant,
the volumetric flow rate at the suction state,
the work done in compression,
the compressor power,
the temperature of the superheated vapour at discharge from the compressor,
the rate of heat rejection at the condenser,
the COP,
the corresponding Carnot COP and
the percentage Carnot cycle efficiency.