标题：Optimization of design and operating parameters on the year round performance of a multi-stage evacuated solar desalination system using transient mathematical analysis
期刊名称：International Journal of Energy and Environment
印刷版ISSN：2076-2895
电子版ISSN：2076-2909
出版年度：2012
卷号：3
期号：3
页码：409-434
出版社：International Energy and Environment Foundation (IEEF)
摘要：The available fresh water resources on the earth are limited. About 79% of water available on the earth is salty, only one percent is fresh and the rest 20% is brackish. Desalination of brackish or saline water is a good method to obtain fresh water. Conventional desalination systems are energy intensive. Solar desalination is a cost effective method to obtain potable water because of freely available clean and green energy source. In this paper, a transient mathematical model was developed for the multi-stage evacuated solar desalination system to achieve the optimum system configuration for the maximum year round performance and distillate yield. The effect of various design and operating parameters on the thermal characteristics and performance of the system were analyzed. It was found that an optimum configuration of four stages with 100mm gap between them when supplied with a mass flow rate of 55kg/m2/day would result in best performance throughout the year. The maximum and minimum yields of 28.044 kg/m2/day and 13.335 kg/m2/day for fresh water at a distillate efficiency of 50.989% and 24.245% and overall thermal efficiency of 81.171% and 40.362% are found in the months of March and December respectively owing to the climatic conditions. The yield decreases to 18.614 kg/m2/day and 9.791 kg/m2/day for brine solution at a distillate efficiency of 33.844% and 17.802% and overall thermal efficiency of 53.876% and 29.635% for March and December respectively The maximum yield of 53.211 kg/m2/day is found in March at an operating pressure of 0.03 bar. The multi-stage evacuated solar desalination system is economically viable and can meet the needs of rural and urban communities to necessitate 10 to 30 kg per day of fresh water.
