氯化锂溶液液滴真空闪蒸过程温度分布特性研究  

Temperature Distribution of LiCl Droplets in Vacuum Flash Evaporation

作　　者：高文忠[1] 时亚茹[1] 曹丹[1] Keith Anderson 

机构地区：[1]上海海事大学商船学院,上海201306 [2]密歇根理工大学,美国密歇根州49931

出　　处：《真空科学与技术学报》2014年第3期197-203,共7页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金项目(51106094)

摘　　要：除湿溶液再生是维持除湿过程持续进行的必备条件,其效率直接影响整个系统的性能。以常用除湿溶液氯化锂为研究对象,在理论分析其液滴闪蒸过程表面温度的变化基础上,进行了实验测试分析。实验结果表明,典型工况下,液滴中心温度和外表面温度变化趋势基本一致,但整个过程两者温度互有高低;绝对压力是影响闪蒸速度的核心因素,压力越低,闪蒸越强烈;在无辐射换热时,液滴初始温度对蒸发所能达到的最低温度影响较小,辐射热对液滴闪蒸过程蒸发强度和热量传递的影响较为显著,不容忽视;液滴闪蒸模型适应于无辐射热影响的绝热闪蒸过程,而兼有辐射热的闪蒸过程则需要对计算结果进行修正。The variations in temperature distribution of LiCI droplet, as a typical dehumidification solution, in vacuum flash-evaporation were theoretically modeled, empirically approximated, and experimentally analyzed to improve its re- cycling efficiency. The influence of the major factors, such as the size and initial temperature of droplet, pressure, and heat radiation,on flash evaporation was evaluated. The experimental results show that the temperatures, at the center and on the surfaces of a droplet, were almost identical except some random fluctuation, under typical evaporation conditions;and that the flash-evaporation rate significantly depends on a decrease of the pressure. The heat radiation was found to have a major impact on theheat transfer and evaporation rate. We suggest that the droplet＇ s flash evaporation model be valid only in adiabatic flash evaporation.

关 键 词：闪蒸 氯化锂 热质传递 辐射 

分 类 号：TK121[动力工程及工程热物理—工程热物理] TB611[动力工程及工程热物理—热能工程]