For the CRC, increasing of the heat source temperature
causes the cooling capacity to increase. This results from the
increasing evaporator temperature which also affects
the refrigerating effect. Furthermore, the increase of the
refrigerant density at the evaporator outlet leads to an
increase of the mass flow rate drawn by the compressor
which results in the increase of the cooling capacity. For the
TPERC, although the temperature difference between the
refrigerant and the water in the evaporator is lower,
the cooling capacity is higher than that of the CRC. This
behavior can be explained in that the overall heat transfer
coefficient of the evaporator in the TPERC is higher than
that of the CRC under the same area of the heat exchanger.
This is because of increases of the wetted area and mass flow
rate in the evaporator and the fact that the evaporator of the
CRC loses some area at the outlet for superheating, while
the evaporator outlet in the TPERC is in a liquid–vapor
mixture condition.