Review Article
Hiroshi Tanaka
Abstract
A tilted wick solar still with a flat plate bottom reflector was analyzed theoretically when there is a gap between the still and reflector at 30oN latitude. A mirror-symmetric plane of the wick relative to the reflector was introduced to calculate the amount of solar radiation reflected from the reflector and absorbed on the wick. Heat and mass transfer in the still were also analyzed to determine the temperature in the still and the distillate production rate of the still. The inclinations of both the still and the reflector should be adjusted adequately for each month and for the gap length in order to increase the distillate productivity. The optimum inclinations of both the still and the reflector throughout the year were determined. The effect of the reflector on distillate productivity decreases with an increase in gap length. However, the distillate productivity can be increased by the reflector even if the gap length is equivalent to that of the still and reflector. The sum of the daily amount of distillate on each month throughout the year was predicted to be increased about 28, 19 and 14% by the reflector when the gap length is 0, 0.5 and 1 m.