Numerical Analysis of a Multi-Stage Evacuation Desalination in Tehran city Makki Mahmoud*, Izadi Abadi Iman**, Jalili Bahram** *Amirkabir University of Technology, Tehran, Iran **Islamic Azad University, Tehran, Iran Online published on 24 April, 2019. Abstract In recent years, drought region has increased in arid and semi-arid areas of the Earth. The types of industrial and nonindustrial desalinations and water reuses in the world have been studied by researchers. In this project, a brief report on the dangers of drought in Iran will be presented in the years to come, then a numerical analysis of an evacuation multi-stage solar still desalination is being studied. The main objective of this paper is the exhaust of non-exhaust gases in the solar-desalination and the effect of this parameter on the production of solar desalination. The exhaust of condensing gases and reducing the internal pressure of each stage lead to increase the doubling of the multi- evacuated multi-stage solar still desalination than multi-stage solar still desalination. The main purpose of this system is numerical analysis and production of desalination for Tehran. The main conclusion from the results is that up to four steps can be used, and the increase in the number of stages after four does not show a reasonable increase in production. The production system for six stages, five stages and four stages for November 2016 in Tehran is 360, 350 and 280 liters per month, respectively. Top Keywords Solar desalination, Solar still, Multistage evacuation distillation, CFD. Top |