Study on longitudinal variation of subcooling with high elevated liquid line in a modular heat pump system

모듈형 동시냉난방 열펌프의 장배관/고낙차에 따른 액선 과냉도 변화에 대한 연구

This study is simulation of high elevated liquid line of a modular heat pump system to observe longitudinal subcooling variation. In a high elevated tube, subcooled refrigerant(R410A) through a condenser changes its states by heat transfer with surrounding air and by pressure drop from elevation. In this study, the liquid line was simulated through correlations of heat transfer and pressure drop for the variation from single-phase into two-phase flow. Pressure drop, heat transfer rate and vapor quality were calculated as key parameters. Two-phase turning heights and variations of the key parameters were confirmed from the simulation. As a result, high elevation of liquid line has great influence on upward flow, which requires additional equipment to compensate the variation.