Clean and highly efficient energy production has long been sought after, as a way to solve global energy and environmental problems. Fuel cells, which convert the chemical energy stored in fuel directly into electrici...Clean and highly efficient energy production has long been sought after, as a way to solve global energy and environmental problems. Fuel cells, which convert the chemical energy stored in fuel directly into electricity, are expected to be a key enabling technology for the pressing energy issues that plague our planet. Fuel cells require oxygen as an oxidant and require oxygen tank containers when used in air-free environments such as outer space and underwater. Hydrogen peroxide has been extensively uti- lized as an alternative liquid oxidant in place of gaseous oxygen. In addition to being an oxidant, hydrogen peroxide can donate electrons in the oxidation reaction to act as a fuel. This article provides an overview of the dual role of hydrogen peroxide in fuel-cell applications, including working principle, system design, and cell performance. Recent innovations and future perspectives of fuel cells that use hydrogen peroxide are particularly emphasized.展开更多
This paper deals with the application of data mining techniques to the conceptual design knowledge for a LV （launch vehicle） with a HRE （hybrid rocket engine）. This LV is a concept of the space transportation, whi...This paper deals with the application of data mining techniques to the conceptual design knowledge for a LV （launch vehicle） with a HRE （hybrid rocket engine）. This LV is a concept of the space transportation, which can deliver micro-satellite to the SSO （sun-synchronous orbit）. To design the higher performance LV with HRE, the optimum size of each component, such as an oxidizer tank containing liquid oxidizer, a combustion chamber containing solid fuel, a pressurizing tank and a nozzle, should be acquired. The Kriging based ANOVA （analysis of variance） and SOM （self-organizing map） are employed as data mining techniques for knowledge discovery. In this study, the paraffin （FT-0070） is used as a propellant of HRE. Then, the relationship among LV performances and design variables are investigated through the analysis and the visualization. To calculate the engine performance, the regression rate is computed based on an empirical expression. The design knowledge is extracted for the design knowledge of the multi-stage LV with HRE by analysis using ANOVA and SOM. As a result, the useful design knowledge on the present design problem is obtained to design HRE for space transportation.展开更多
基金fully supported by a grant fromthe Research Grants Council of the Hong Kong Special Administrative Region,China(HKUST9/CRF/11G)
文摘Clean and highly efficient energy production has long been sought after, as a way to solve global energy and environmental problems. Fuel cells, which convert the chemical energy stored in fuel directly into electricity, are expected to be a key enabling technology for the pressing energy issues that plague our planet. Fuel cells require oxygen as an oxidant and require oxygen tank containers when used in air-free environments such as outer space and underwater. Hydrogen peroxide has been extensively uti- lized as an alternative liquid oxidant in place of gaseous oxygen. In addition to being an oxidant, hydrogen peroxide can donate electrons in the oxidation reaction to act as a fuel. This article provides an overview of the dual role of hydrogen peroxide in fuel-cell applications, including working principle, system design, and cell performance. Recent innovations and future perspectives of fuel cells that use hydrogen peroxide are particularly emphasized.
文摘This paper deals with the application of data mining techniques to the conceptual design knowledge for a LV （launch vehicle） with a HRE （hybrid rocket engine）. This LV is a concept of the space transportation, which can deliver micro-satellite to the SSO （sun-synchronous orbit）. To design the higher performance LV with HRE, the optimum size of each component, such as an oxidizer tank containing liquid oxidizer, a combustion chamber containing solid fuel, a pressurizing tank and a nozzle, should be acquired. The Kriging based ANOVA （analysis of variance） and SOM （self-organizing map） are employed as data mining techniques for knowledge discovery. In this study, the paraffin （FT-0070） is used as a propellant of HRE. Then, the relationship among LV performances and design variables are investigated through the analysis and the visualization. To calculate the engine performance, the regression rate is computed based on an empirical expression. The design knowledge is extracted for the design knowledge of the multi-stage LV with HRE by analysis using ANOVA and SOM. As a result, the useful design knowledge on the present design problem is obtained to design HRE for space transportation.
