Experimental investigation on a new method of regenerating dehumidification solution–release solution droplet into vacuum

Flash evaporation, as a new method to regenerate dehumidification solution, is investigated in this paper. Droplets of lithium chloride and/or calcium chloride solution were suspended on the junction of a thermocouple, whose characteristic change was captured by high-speed camera, infrared camera, and thermocouple, and analyzed by comparing the values of different conditions. The results indicate that the pressure determines the degree of superheat, and the absorbed heat affects the intensity of the evaporation. A stronger surface tension caused by an increase in concentration or in change of solute weakens the intensity of water evaporation; a higher initial droplet temperature improves the evaporation intensity in the beginning stage, having no influence on its final temperature. The smaller the droplet diameter, the lower the minimum temperature is; radiant heat plays a decisive role in the process of flash evaporation, which is almost the only heat source provided to the droplet for evaporation in the stable stage.