The schematic diagram of experimental setup is shown in Fig. 3.
The test is based on the enthalpy difference method. The evaporator
is installed in the indoor test room. Four platinum resistance
thermometers with an uncertainty of ±0.1 C are set to measure the
dry-bulb temperature (DB) and wet-bulb temperature (WB) of the
inlet and outlet air. The air flow rate of the evaporator is determined
by a nozzle flowmeter. The pressure difference across the nozzle is
measured by a differential pressure transducer with an uncertainty
of ±0.5%. The other parts of the system are installed in the outdoor
test room. The DB and WB of the inlet air are measured. The input
power of the compressor and fans are measured by a power meter
with an uncertainty of ±0.5%. The input power of the three operation
modes is given by the following equations