Indoor experiments of the vertical multiple-effect diffusion-type solar still coupled with a heat-pipe solar collector

Indoor experiments were performed for the vertical multiple-effect diffusion-type solar still that consists of a number of vertical partitions in contact with saline-soaked wicks with narrow air gaps between partitions, coupled with a heat-pipe solar collector, using heating lamps instead of actual solar radiation. The size of the proposed still is very compact, and the thickness is less than or equal to about 10 cm when it is carried or in storage; furthermore, the proposed still was predicted to produce a greater amount of distilled water than that of a conventional multiple-effect diffusion-type still without electricity. The predicted time variation of temperatures of the collector plate of the solar collector and the first and the second partitions of the single-effect still were in good agreement with the experimental results, and the experimental results of the overall production rates of the multiple-effect still were about 93% of what was predicted. This indicates that the heat pipe of the proposed still can transport thermal energy well from the solar collector to the vertical multiple-effect diffusion-type still.

We performed indoor experiments with a vertical multiple-effect diffusion-type still coupled with a heat-pipe solar collector, and the results of this work are summarized as follows: C Time variations of the temperatures of the collector plate and the first and the second partition are in fairly good agreement between the experimental results and predicted ones, and this indicates that the heat pipe of the proposed still transports thermal energy well from the solar collector to the first partition. C The discrepancy between the experimental results and prediction for the temperature difference between the collector plate and the first partition as well as the distillate production rate on the second partition would be larger at lower radiation levels on the glass cover from the heating lamps, and this may be caused by the fact that dry patches occur more often on the inner surface of the upper section of the evaporating tubes at lower radiations, since the interval of periodic sudden boiling would be longer for the lower radiation.