The thermal efficiency improvement of a steam Rankine cycle by innovative design of a hybrid cooling tower and a solar chimney concept

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• 作者：Arash Zandian ; ^{arash.zdn@gmail.com} ; ^{azandian@uci.edu} ; Mehdi Ashjaee¹ ; ^{ashjaee@ut.ac.ir}
• 关键词：Solar chimney ; Dry cooling tower ; Thermal efficiency ; Power output ; CFD
• 刊名：Renewable Energy
• 出版年：2013
• 出版时间：March, 2013
• 年：2013
• 卷：51
• 期：Complete
• 页码：465-473
• 全文大小：860 K

文摘

In the present work, a dry cooling tower and a solar chimney design are recombined in order to increase the thermal efficiency of a steam Rankine cycle. The rejected heat from the condenser into the dry cooling tower supplemented by the solar radiation gained through its transparent cover are the sources of wind energy generation that is captured by a wind turbine which is located at the beginning of the chimney. In this research a case study for a 250?MW steam power plant of Shahid Rajaee in Iran has been performed. A CFD finite volume code is developed to find the generated wind velocity at the turbine entrance for a 250?m dry cooling tower base diameter and a chimney height of 200?m. Calculations have been iterated for different ambient temperatures and solar irradiances, representing temperature gradient within day length. A range of 360?kW to 3?MW power is obtained for the change in the chimney diameter from 10 to 50?m. The results show a maximum of 0.37 percent increase in the thermal efficiency of a 250?MW fossil fuel power plant unit; which proves this design to be a significant improvement in efficiency of thermal power plants, by capturing the heat that is dissipated from dry cooling towers.