TY - JOUR
TI - Development of a compression-absorption heat pump system for utilizing low temperature geothermal water
AU - Gong Yulie
AU - Luo Chao
AU - Lu Zhenneng
AU - Yao Yuan
AU - Ma Weibin
JN - Thermal Science
PY - 2019
VL - 23
IS - 2
SP - 791
EP - 799
PT - Article
AB - Heat pump is an effective way to use the low-temperature geothermal water  with temperature lower than 50°C for building heating. Compared to the  conventional vapor compression heat pump, the compression-absorption heat  pump (CAHP) can obtain higher heat sink temperature with lower compression  ratio. Besides, the temperature glide in the generator and absorber of CAHP  can be fitted to the heat source and heat sink, which achieves better COP.  Two models, respectively, for the generator and whole system using  ammonia-water as the working fluid are proposed, and the effects of  different concentration of strong solution, cycle ratios, heat source  temperature and spray density on the generator are investigated. The  objective is to analyze the performance of CAHP system driven by  low-temperature geothermal water. The results show that the maximum of  overall heat transfer coefficient of the vertical out-tube falling film  generator can be obtained with the optimum spray density of around 0.16  kg/(m•s) and there is an optimum concentration of around 65% for the CAHP  system. When the low heat source temperature between 30 and 40°C,the high  heat sink temperature can reach to 65-70°C.