The Performance of Ground Source Heat Pump System for Domestic Heating under various Ground Water Circulation Conditions

저에너지주택내 지중순환수 조건 변화에 따른 지열 히트펌프의 동절기 성능평가

This study is evaluates the performance of a prototype ground source heat pump(GSHP) system under various secondary fluid flow rates. The prototype GSHP has four functions : space heating, cooling, floor heating and domestic water heating. Heating can be operated by two operational modes : water to water and water to air. As a result, the COP of GSHP was increased from 3.43 to 3.84 when the underground circulation flow rate was increased, but ratio of increased in COP was decreased. When the flow rate of the GSHP system including electricity consumption of the ground circulation pump was increased 19.2 LPM to 47.4 LPM, the COP was increased by up to 6.1%, but flow rate was increased 47.4 to 87.7 LPM, the COP was decreased by up to 6.2%. It is suggested that the GSHP with an underground circulation inverter pump saves power consumption in the operation mode, a variable-speed control of ground circulation flow rate based on a compressor Hz have to be selected in order to optimize COP of GSHP system.