Inspection of hydrogen generation from water using rapid compression and expansion machine

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K13884
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Thermal engineering
• Research Institution: University of Toyama
• Principal Investigator: Tezaki Atsumu 富山大学, 大学院理工学研究部(工学), 教授 (50236965)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 水素生成 / 熱分解 / 化学平衡 / 反応機構 / 断熱圧縮 / 急速膨張

Outline of Final Research Achievements

Hydrogen generation using rapid compression and expansion of water containing gas mixture was theoretically investigated. Experimental methods to implement the concept were also discussed. High temperature such as 3000K, at which water is thermally decomposed to form hydrogen, can be achieved by adiabatic compression of rare gas based mixture with a reasonable compression ratio around 10, if the mixture is preheated to around 1000K. Chemical kinetic simulations with a detailed reaction model of H2-O2 system were conducted to estimate composition change upon cooling from that of equilibrium at high temperature. It was found that a rapid cooling within 0.1 ms to temperature at or below 800K is necessary to obtain residual hydrogen. This cooling rate is too fast for mechanical expansion method to realize, consequently another non-mechanical method, such as supersonic free expansion should be introduced.

Free Research Field

熱工学