18 May 2017

O.1.7.4 Modeling and Experimental Investigations on Performance of Water Tanks in Circulating Heat Pump Water Heaters

The heat pump water heater (HPWH) is a promising technology due to its high performance and
environment–friendliness. The water tank is an important part of a HPWH, and temperature
distributions are essential in control strategy designing and assessment of the usable hot water
volumes. This study aims to describe the effects of control strategies on temperature distributions in a
water tank and the effects of flow rates on usable hot water volumes through CFD calculations and
experiments. Results showed that the simulations were in good consistency with experiments and the
temperature stratification was better in circulating heating for once than that for twice. A correlation
was established to compute the real-time volume of usable hot water in a continuous water tapping.