溴化锂对NH_3-H_2O-LiBr三元溶液特性作用机理的初步研究  

Mechanism of Action of LiBr on Characteristics of NH_3-H_2O-LiBr Ternary Solution

作　　者：何树青[1] 吴铁晖[1] 吴裕远[1] 王晶[1] 吴红林[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2008年第7期848-851,共4页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(50776064)

摘　　要：针对目前吸收式制冷领域中研究的NH3-H2O-LiBr三元溶液混合工质,采用溶剂化作用模型和电解质NRTL方程,研究了溴化锂(LiBr)对溶液组成的影响.结果表明:随着LiBr初始摩尔分数的升高,水的溶剂化系数m先升高,后略有降低,氨的溶济化系数n始终呈下降趋势,并且在350 K、LiBr的初始摩尔分数大于0.03时m>n,离子溶剂化作用形成的离子簇包含的水分子多于氨分子;溶剂化作用后水的含量高于作用前的,但前后差值随LiBr初始摩尔分数升高而减小;随着温度的升高,m降低,n升高,离子吸引水分子的能力减弱而吸引氨分子的能力升高;完全电离的溶剂化模型只在LiBr的初始摩尔分数小于0.1时得到较好的结果,在LiBr的初始摩尔分数大于0.1时与部分电离模型产生较大的误差.A solvation model and electrolyte NRTL equation were used to study the mechanism of the action of LiBr on the thermal equilibrium characteristics of NH3-H2O-LiB in an absorption refrigeration system. The results show that the solvation number m, water molecules arrested in ionic clusters, increases with the increases of the original mole concentration of LiBr and then decreases slightly when the mole concentration is higher than 0.13. The solvation number n, ammonia molecules arrested in ionic clusters, decreases in the whole range. Moreover, m〉n when the mole concentration is greater than 0. 03. In addition, the mole concentration of water after salvation is also higher than that before solvation, but their value difference decreases significantly with the increase of the original mole concentration of LiBr. Large difference between the results obtained by the completely ionization solvation model and the partial ionization one occurs when the original concentration of LiBr surpassed 0. 1.

关 键 词：吸收式制冷 溶剂化作用 NH3-H2O-LiBr 离子簇 

分 类 号：TB651[一般工业技术—制冷工程]