TY - JOUR
TI - Heat-transfer characteristics of ammonia-water falling film generation outside a vertical tube
AU - Luo Chao
AU - Zhao Jun
AU - Ma Weibin
JN - Thermal Science
PY - 2017
VL - 21
IS - 3
SP - 1251
EP - 1259
PT - Article
AB - A heat transfer experimental of vertical out-tube falling film was conducted with different inlet spray density of ammonia-water solution and inlet hot water temperature. The inlet liquid mass concentration was selected as 60% of ammonia. The experiments showed that the overall heat transfer coefficient increases with the increase of inlet spray density and a maximum overall heat transfer coefficient could be obtained in an optimum spray density of ammonia-water solution, Γ, between 0.26 and 0.29 kg/ms. The generation of ammonia vapor outside the vertical falling film had a similar trend with the overall heat transfer coefficient basing on different spray density. The effect of hot water temperature difference, ΔT, on overall heat transfer coefficient showed that ΔT between 10 and 13 K is the optimum temperature difference of the vertical falling film generation