Design and Evaluation of a New Absorber Plate for Cascade Solar Still

Productivity enhancement of solar stills has been one of the main goals of the researchers. In this study, a new approach to design of solar still absorber plate was developed and its effect on the productivity process was investigated theoretically and experimentally . A mathematical model was developed to calculate the theoretical productivity of the solar still with a stepped absorber plate. Comparison between the theoretical and experimental results was considered. It was found that the results of the developed mathematical model were in good agreement with the experimental results. According to the mathematical model, it was concluded that the use of absorber plate with a new pattern for cascade solar still caused 18% and 22% increase in the amount of absorbed solar intensity in spring and summer seasons, respectively, as compared with the ordinary type absorber plate. The values of the absorbed energy for the two types of absorber plates were identical in autumn and winter.