Heat Pump

No. 1: Heat Pump Experiment
1. Objective
The objective of the experiment is to measure the Coefficient of Performance (COP) of a Heat Pump.
2. The experimental setup
The equipment provided is a heat pump with pressure and temperature sensors placed at various locations.
3. Procedure
Study the diagram and equipment provided and identify the various components of the Heat Pump – that is, the compressor (1-2), the condenser (2-3), the expansion valve (3-4) and the evaporator (4-1) and the locations of the pressure and temperature sensors.
Using 1 cooling fan at the evaporator (4-1), varying the water flow rate to the heat exchanger of the condenser (2-3) by turning the water control valve to the heat exchanger. Vary the water flow rate to give you 5 readings (from 15 litres/min to 7 litres/min). After each adjustment, allow the system to run for 10 minutes to stabilize before taking any reading.
Repeat the experiment using 2 cooling fans at the evaporator.
4. Results
Tabulate your results in the following table. Calculate the coefficient of performance and compared with the ideal coefficient of performance.
Readings Condenser Pressure, P c
Evaporator Pressure, P e
Heat exchanger inlet temperature, Tin
Heat Exchanger outlet temperature, Tout
Heat Exchanger water flow rate, m
&
bar bar deg C deg C litres/min 1 2 3 4 5 6
Calculate
(a) The heat transfer rate from the condenser q1 = m
&
C (T o – Ti) kJ/s where m
&
is the water mass flow rate (kg/s) and C = 4.2 kJ/kg K
(b) The measured coefficient of performance
(c) The ideal coefficient of performance using T a and T b
Plot the measured and ideal COPs against the water mass flow rate (litres/min).
5. Discussion & Conclusions
Discuss the performance of a practical Heat Pump and compare with the ideal