The paper presents the results of the experimental research which was carried out on the spark ignition engine, experimental model, fuelled with hydrogen by direct injection method, using qualitative load adjustment m...The paper presents the results of the experimental research which was carried out on the spark ignition engine, experimental model, fuelled with hydrogen by direct injection method, using qualitative load adjustment method for engine running control. Also, the hydrogen injection solution at the beginning of the compression stroke, after the inlet valve closing, assures the cylinder cooling by inlet air avoiding in that way uncontrolled ignition phenomena and inlet back fire. Using this fueling method avoided the abnormally hydrogen combustion phenomena＇s for stoichiometric dosage operating conditions, achieving -30 % engine power increase. Hydrogen engine runs with very lean mixtures, due to engine load qualitative adjustment, a dosage value that leads to a reduction of the engine power with -25% from maximum power value. This provides a higher engine efficiency at low loads, the best results was obtained for λ=2- 4 air-fuel ratio values. The influence of the mixture quality on burning process, on polluting and energetically engine performances at the fuelling with hydrogen using direct injection method are presented. Because of the higher combustion temperature, the NOx emission level is higher for λ=1 - 2 comparative to gasoline fuelled engine, but decreases a lot for leaner mixture values, λ〉2.5.展开更多
华硕W90华硕最新推出的终极娱乐航母W90,为我们带来了2009最具颠覆力的至尊娱乐体验!它不仅是世界第一台3D mark 06可达惊世15000+分的笔记本,世界第一台具有3组SO-DIMM设计的笔记本,同时也是世界第一台配备200万自动聚焦摄像头的笔记...华硕W90华硕最新推出的终极娱乐航母W90,为我们带来了2009最具颠覆力的至尊娱乐体验!它不仅是世界第一台3D mark 06可达惊世15000+分的笔记本,世界第一台具有3组SO-DIMM设计的笔记本,同时也是世界第一台配备200万自动聚焦摄像头的笔记本……这款笔记本拥有获得2009德国红点设计大奖的特制巧克力键盘,采用19.02毫米最佳间距和键位间距紧密设置,并依据人体工学特征设计出凹帽状按键,一方面以接近体表温度的温柔触感,另一方面也能有效避免积尘和防护液体泼溅。在显示方面,W90Vp在ATI CrossFireX m技术助力下,结集两块ATI Mobility Radeon<sup>TM</sup>HD4870新一代顶级独立显示芯片,以及GDDRⅢ1GB独立显存,支持CrossFireX技术并拥有全球首配3×SO-DIMM插槽设计。在3D效能爆发力被点燃的同时,W90针对整机运行动力也做了全方位的提效、减耗工作。全球首配3×SO-DIMM插槽设计,使这款机器在DDRⅡ800频率下能够达到最高6GB的内存容量;配合英特尔（?）Core<sup>TM</sup>2 Duo processor T9600/T9400/P8600/P8400市面顶尖处理器,激发出无可比拟的运行能量。特别配备的双硬盘驱动器,更能提供最高达1 TB的存储容量,协同Blu-Ray光驱,各类文件和多媒体资源尽可无限量存储。展开更多
文摘The paper presents the results of the experimental research which was carried out on the spark ignition engine, experimental model, fuelled with hydrogen by direct injection method, using qualitative load adjustment method for engine running control. Also, the hydrogen injection solution at the beginning of the compression stroke, after the inlet valve closing, assures the cylinder cooling by inlet air avoiding in that way uncontrolled ignition phenomena and inlet back fire. Using this fueling method avoided the abnormally hydrogen combustion phenomena＇s for stoichiometric dosage operating conditions, achieving -30 % engine power increase. Hydrogen engine runs with very lean mixtures, due to engine load qualitative adjustment, a dosage value that leads to a reduction of the engine power with -25% from maximum power value. This provides a higher engine efficiency at low loads, the best results was obtained for λ=2- 4 air-fuel ratio values. The influence of the mixture quality on burning process, on polluting and energetically engine performances at the fuelling with hydrogen using direct injection method are presented. Because of the higher combustion temperature, the NOx emission level is higher for λ=1 - 2 comparative to gasoline fuelled engine, but decreases a lot for leaner mixture values, λ〉2.5.
