Biophysical Evaluation of an Evaporatively-Cooled Water Bag

摘要

Commercially available flax canvas water bags were evaluated for their ability to cool drinking water by evaporating water from their outer surfaces. Evaluations were conducted in an environmentally-controlled chamber under various climatic conditions. Different ambient temperatures, relative humidities and wind velocities were utilized to create climatic conditions normally observed in Southwest Asia during the summer months (June through September). Water which was initially above or below ambient temperature approached an equilibrium temperature (Tae) in the water bag which was at or near the chamber wet-bulb temperature (Twb) in 2 to 5 hours, depending on the wind speed. High wind velocities (WV) over the water bags were responsible for large total water volume losses which could be significant in a combat situation involving extended desert maneuvers in remote regions. (Author)