In this study، a traditional air source heat pump was modified by adding secondary
evaporator within hot water tank which acted as a water heat source of the heat pump. We
made the heat pump to run alternatively either using surrounding air heat or
water heat
gained from solar power.
We have done experiments during five months starting in December of 2014 until
April 2015. Temperature and pressure were measured at specific points of the cycle. Then
we defined the enthalpy at each point for both cycles using EES software (which is a
software to simulate thermodynamic elements)، and calculated the amounts of heat gained
in the evaporator، heat charged from the condenser، compressor work، coefficient of
performance ، and electrical power consumed by the compressor.
Then we made a compare between the two cycles and found that the improvement
ratio in of the modified cycle to the traditional cycle was 77.07%، and the reduction
ratio in electrical power consumed by the compressor of the modified cycle was 33.54%.
