Abstract
To improve the system performance of a gas engine driven heat pump (GHP) system, an analytical modeling and experimental study has been made by using desiccant system in cooling operation (particularly in high humidity operations) and suction line waste heat recovery to augment heating capacity and efficiency. The performance of overall GHP system has been simulated with a detailed vapor compression heat pump system design model. The modeling includes: (1) GHP cycle without any performance improvements (suction liquid heat exchange and heat recovery) as a baseline (both in cooling and heating mode), (2) the GHP cycle in cooling mode with desiccant system regenerated by waste heat from engine incorporated, (3) GHP cycle in heating mode with heat recovery (recovered heat from engine). According to the system modeling results, by using the desiccant system the sensible heat ratio (SHR- sensible heat ratio) can be lowered to 40%. The waste heat of the gas engine can boost the space heating efficiency by 25% at rated operating conditions. In addtion,using EnergyPlus, building energy simulations have been conducted to assess annual energy consumptions of GHP in sixteen US cities, and the performances are compared to a baseline unit, which has a electrically-driven air conditioner with the seasonal COP of 4.1 for space cooling and a gas funace with 90% fuel efficiency for space heating.
