Performance analysis and experimental verification of a multi-sleeve tubular still filled with different gas media

A novel nonconcentrical multi-sleeve tubular still for triple-effect solar desalination device is described in this study. An experimental and analytical analysis is given to investigate how the water production performance is affected by different gas media, which are air, oxygen, helium and carbon dioxide. The water production rate and the temperature value of every measured point inside the device with different gas media were obtained through the experiments. Experimental results show that, when the heating temperature is 85 °C and the gas medium is oxygen, the water production rate can reach to 0.58 kg·h− 1. It is increased by 31.82% compared with the rate when the gas medium is air. In addition, the internal heat and mass transfer mechanism of the device with different gas media was analyzed. The semi-empirical expression of the water production rate is given. According to the experimental data, the Dv under different conditions is obtained. The results obtained are then compared against the experimental results, and it is found that the trend of theoretical water production rate is consistent with the experimental results. The reasons for deviation are analyzed.