Wendelstein 7-AS (W7-AS) pertains to an advanced helical stellarator. A new fuelling method, the supersonic molecular beam injection (SMBI, named Gas Jet in Germany) system was installed in W7-AS in May 2001 as a coop...Wendelstein 7-AS (W7-AS) pertains to an advanced helical stellarator. A new fuelling method, the supersonic molecular beam injection (SMBI, named Gas Jet in Germany) system was installed in W7-AS in May 2001 as a cooperation research item co-supported by the National Nature Science Foundation of China and the Max-Planck Institute of Plasma Physics, Garching, Germany. The experiments of the gas jet with hydrogen or deuterium on W7-AS were implemented. The experimental results exhibit the following features such as high fuelling efficiency, stable high-density plasmas and reduction of the recycling fluxes from the vessel wall during injection. These crucial points show that the new fuelling method can be applied to long and stable discharges.展开更多
Coherent jets are widely used in electric are furnace (EAF) steelmaking to increase the oxygen utilization and chemical reaction rates. However, the influence of fuel gas combustion on jet behavior is not fully unde...Coherent jets are widely used in electric are furnace (EAF) steelmaking to increase the oxygen utilization and chemical reaction rates. However, the influence of fuel gas combustion on jet behavior is not fully understood yet. The flow and combustion characteristics of a coherent jet were thus investigated at steelmaking temperature using Fluent software, and a detailed chemical kinetic reaction mecha- nism was used in the combustion reaction model. The axial velocity and total temperature of the supersonic jet were measured via hot state experiments. The simulation results were compared with the experimental data and the empirical jet model proposed by Ito and Muchi and good consistency was obtained. The research results indicated that the potential core length of the coherent jet can be prolonged by optimizing the combustion effect of the fuel gas. Besides, the behavior of the supersonic jet in the subsonic section was also investigated, as it is an important factor for controlling the position of the oxygen lance. The investigation indicated that the attenuation of the coherent jet is more notable than that of the conventional jet in the subsonic section.展开更多
基金The project supported by the National Nature Science Foundation of China (Nos. 19775011 and 10075016) the China Nuclear Industry Science Foundation (No. 94C03033)
文摘Wendelstein 7-AS (W7-AS) pertains to an advanced helical stellarator. A new fuelling method, the supersonic molecular beam injection (SMBI, named Gas Jet in Germany) system was installed in W7-AS in May 2001 as a cooperation research item co-supported by the National Nature Science Foundation of China and the Max-Planck Institute of Plasma Physics, Garching, Germany. The experiments of the gas jet with hydrogen or deuterium on W7-AS were implemented. The experimental results exhibit the following features such as high fuelling efficiency, stable high-density plasmas and reduction of the recycling fluxes from the vessel wall during injection. These crucial points show that the new fuelling method can be applied to long and stable discharges.
基金support by the National Natural Science Foundation of China(NSFC 51474024and 51334001)National Key Technology Research and Development Program of the 12th Five-year Plan of China(12FYP 2015BAF03B01)
文摘Coherent jets are widely used in electric are furnace (EAF) steelmaking to increase the oxygen utilization and chemical reaction rates. However, the influence of fuel gas combustion on jet behavior is not fully understood yet. The flow and combustion characteristics of a coherent jet were thus investigated at steelmaking temperature using Fluent software, and a detailed chemical kinetic reaction mecha- nism was used in the combustion reaction model. The axial velocity and total temperature of the supersonic jet were measured via hot state experiments. The simulation results were compared with the experimental data and the empirical jet model proposed by Ito and Muchi and good consistency was obtained. The research results indicated that the potential core length of the coherent jet can be prolonged by optimizing the combustion effect of the fuel gas. Besides, the behavior of the supersonic jet in the subsonic section was also investigated, as it is an important factor for controlling the position of the oxygen lance. The investigation indicated that the attenuation of the coherent jet is more notable than that of the conventional jet in the subsonic section.