Full Description

This paper will discuss the development of a finite-volume model for a heat pump water heater wraparound condenser. To allow for fast simulation time, the tank-to-water heat transfer coefficient is predicted using correlations rather than CFD simulation. Validation of the condenser model against experimental data for two different existing heat pump water heater designs has shown very good agreement with the simulated results. The tool has been incorporated into a complete system model including a finite-volume evaporator, map-based compressor, expansion device, and pipes. Future work will allow this steady-state vapor compression cycle model to be solved iteratively to approximate the dynamic changes to the water temperature profile over time. The approach provides accurate heat transfer predictions with little development and simulation time as compared to experimental or CFD efforts, which are often used for water heaters.

Citation: ASHRAE Papers: 2015 ASHRAE Annual Conference, Atlanta, GA