摘要
对1.5kW NH3-H2O-LiBr吸收式制冷机的吸收和蒸发性能进行了实验研究.实验共采用20组溶液,其中氨的质量分数分别为50%、55%和60%,LiBr的质量分数范围为0～50%.有关吸收性能的实验结果表明,LiBr的加入并不能一直降低吸收压力,当LiBr浓度增大到一定值时,吸收压力反而升高,导致吸收效果恶化,此时的LiBr浓度称为吸收压力LiBr拐点浓度,且随着氨浓度的升高,该LiBr拐点浓度减小.有关蒸发性能的实验结果表明,发生器溶液中氨浓度一定时,相同温度下蒸发器内蒸发压力随着LiBr浓度的升高均先增大后减小.有关系统性能系数的实验结果表明,发生器溶液中氨浓度一定时,系统性能系数随着LiBr浓度的升高均先增大后减小.当w(NH3)为60%、w(LiBr)为30%时,系统最大性能系数为0.402,较二元NH3-H2O机组提高了30.94%,说明该实验结果可指导NH3-H2O-LiBr三元溶液在吸收式制冷机中的应用.
Experiments were carried out on the absorption and evaporation performance of an NH3-H2O-LiBr absorption chiller with a refrigerating capacity of 1.5 kW.Twenty groups of solutions were tested in the experiment with different NH3 concentration of 50%,55% and 60% and the LiBr concentration from 0 to 50%.The results show that the absorption pressure would not consistently decrease with an increase in LiBr in the solution.When the LiBr concentration reached an inflexion value,the absorption pressure would rise,leading to the deterioration of the absorption process,and the LiBr inflexion value would decrease with an increase in NH3 concentration.Moreover,the evaporation pressure would rise at first and then decline with an increase in LiBr concentration when the NH3 concentration in the generator and the temperature in the evaporator were unchanged during the process.In addition,the COP would increase at first and then decrease with an increase in LiBr concentration at certain NH3 concentration in the generator.The maximum COP of the system with the NH3 concentration of 60% and the LiBr concentration of 30% was 0.402,30.94% higher than that of an NH3-H2O refrigeration system.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2011年第3期40-43,116,共5页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(50776064)
关键词
氨-水-溴化锂
吸收式制冷机
吸收性能
ammonia-water-lithium bromide
absorption chiller
absorption performance
