共查询到20条相似文献，搜索用时 156 毫秒
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惠州的赖女士在接女儿回家的途中,因为下雨路滑,车辆撞上护栏起火,赖女士想冒险取回车里的贵重物品,却被女儿劝住。女儿安慰妈妈:只要人没事就好。赖女士听了女儿的安慰后,心情逐渐平复下来。赖女士的女儿,在遭遇车辆起火时,没有害怕大哭,反倒安慰起妈妈来,不是因为她不为车辆起火而难过,而是她在获益框架下思考,比起注重失去了什么,更加注重得到了什么。 相似文献
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★家具、被褥等起火:—般用水灭火。用身边可盛水的物品如脸盆等向火焰上泼水,也可把水管接到水龙头上喷水灭火;同时把燃烧点附近的可燃物泼湿降温。★电器起火:家用电器或线路着火,要先切断电源,再用干粉或气体灭火器灭火,不可直接泼水灭火,以防触电或电器爆炸伤人。★电视机起火:电视机万一起火,决不可用水浇,可以在切断电源后,用棉被将其盖灭。灭火时,只能从侧面靠近电视机,以防显像管爆炸伤人。若使用灭火器灭火,不应直接射向电视屏幕,以免其受热后突然遇冷而爆炸。★油锅起火:油锅起火时应迅速关闭炉灶燃气阀门,直接盖上锅盖或用湿抹布… 相似文献
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以北京某地铁典型站台为研究对象,采用火灾动力学模拟软件FDS对站台中部起火和端部起火两种情况进行模拟,对热辐射、CO浓度、温度、能见度、烟层高度等值的变化进行了分析.结合现行地铁设计规范,得到站台中部起火时,“火源上方风机排烟,站台风机送风”方式;站台端部起火时,“A、C、E风机排烟,D风机送风”方式下,能确保在站台较大区域内烟气浓度值一定时间内较小,火场热释放速率、温度及CO含量等参数最优,提出了地铁在火灾工况下最优化通风方式. 相似文献
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《聪明泉(少儿版)》2007,(10)
那是6年前的事了。美国费城一户人家,无端起火。瞬间火光冲天,救火车呼啸而来,警戒线外,是呼天抢地的母亲科瑞斯,家里有她出生仅10天的宝宝。她去附近的超市买婴儿尿片,走时,宝宝的睡态是那样沉醉,哪想到竟会起火? 相似文献
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模拟了一种常规快速式燃气热水器的燃烧系统,研究了不同压力状况下的燃烧工况.得到的数值模拟结果与实验获得的数据吻合得较好,证明了所用物理模型和数学模型的合理性.结果显示,火焰高度和过剩空气系数依赖于系统出口和入口的静压差,而与燃烧室内的绝对压力无关.该静压差和系统中用于燃烧的空气量显著影响CO的生成,与CO的生成量呈反比关系,并同时影响燃烧区域内的温度场和速度场.为降低CO排放水平,必须增加进入燃烧系统的空气量,因此需要增加风机输出功率以提供足够的空气压头.该研究为设计快速式燃气热水器提供了一种行之有效的方法. 相似文献
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我国垃圾水分大、热值低、灰分大、成分复杂,焚烧炉燃烧控制不可控因素多,结合TIF-CFB特点,从垃圾品质、助燃煤成分、过量空气系数、负荷变化等参数分析影响垃圾燃烧稳定性的因素,对垃圾焚烧中产生的二恶英、重金属、酸性气体、固体废物等进行解析利于有针对性地防治,可实现垃圾发电最大的环境效益。 相似文献
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Experimental Study on Dimethyl Ether Combustion Process in Homogeneous Charge Compression Ignition Mode 总被引：2，自引：0，他引：2
Experimental study on homogeneous charge compression ignition (HCCI) combustion process was carried out on a single-cylinder direct injection diesel engine fueled with dimethyl ether(DME). The influence of inert gas CO2 on the ignition and combustion process was investigated. The research results indicate that because of the high cetanc number of DME, the stable HCCI operating range is quite narrow while the engine has a high compression ratio. The HCCI operating range can be largely extended when the inert gas is inducted into the charging air. HCCI combustion of DME presents remarkable characteristic of two-stage combustion process. As the concentration of inert gas increases, the ignition timing of the first combustion stage delays,the peak heat release rate decreases, and the combustion duration extends. Inducting inert gas into charging air cannot make the combustion and heat release of DME occur at a perfect crank angle position. Therefore, to obtain HCCI operation for the fuel with high cetane number,other methods such as reducing engine compression ratio should be adopted. Emission results show that under HCCI operation, a nearly zero NOx emission can be obtained with no smoke emissions. But the HC and CO emissions are high, and beth rise with the increase of the concentration of inert gases. 相似文献
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电站锅炉效率与最佳过量空气系数的研究 总被引：1，自引：0，他引：1
针对锅炉优化运行,结合锅炉运行的主要参数及实验所得的数据,使用反平衡、控制变量等方法,综合分析排烟热损失、化学不完全燃烧热损失、固体不完全燃烧热损失,以及锅炉燃烧效率与过量空气系数和锅炉运行参数的关系,建立最佳过量空气系数和锅炉效率反平衡等模型,使用Matlab、Excel等软件,得到锅炉运行的最佳过量空气系数及锅炉效率与过量空气系数的关系. 相似文献
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对黄冈市城区近5年来造成空气污染的三个主要因子SO2、NO2和TSP的连续监测结果进行了系统分析，发现SO2年日平均浓度值的变化呈下降趋势，而NO2和TSP年日平均浓度值的变化呈上升趋势，该地区的空气污染已从煤烟型污染向煤烟－－汽车尾气混合型污染转变。从继续控制煤烟型污染，加强控制汽车尾气污染、扬尘污染和工业污染等四个方面提出了防治对策。 相似文献
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任瑞忠 《辽宁科技学院学报》2014,(3):6-7
北营新1号高炉通过优化高炉煤气处理流程,配置旋切顶燃式热风炉,采用前置预热炉、热管换热器分别预热助燃空气和煤气,使用带横梁的炉箅子技术、管道保温技术以及优化烧炉技术等,为送风温度达到1250℃创造了条件。高炉在精料基础上,通过控制合理炉腹煤气量指数和理论燃烧温度,优化煤气流分布,规范高炉操作等措施,2013年全年平均风温1248℃,达到国内同型高炉领先水平。 相似文献
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Gas flows and particle mass flux were measured and clutriation experimentswere conducted in two cold test models of vortexing fluidized bed(VFB).The experimen-tal results show that the secondary air injected tangentially creates strong vortexes,estab-lishes particle suspension layers and internal circulation,and suppresses the elutriation offine particles greatly.The vortexing fluidized bed combustion has bright prospect bccauseof its much higher combustion efficiency and desulphidation efficiency than bubblingfluidized bed combustion due to long particle residence time and high slip velocity betweengas and solid,and its simpler configuration and lower cost than circulating fluidized bedcombustion. 相似文献
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Temperature is the most important parameter for the improvement of combustion efficiency and the control of pollutants. In order to obtain accurate flame temperatures in a rotary kiln incinerator using non-intrusive thermographic method, the effective flame emissivity was studied. A combined narrow- and wide-band model and Mie scattering method were used to calculate the radiative properties for gases and fly-ash particles under different combustion conditions. The effects of the air/waste ratio and fly-ash particles on the effective flame emissivity were discussed. The results of numerical calculations showed that the effective emissivity decreased from 0.90 to 0.80 when the air/waste ratio increased from 1.0 to 1.8, and the effect of the fly-ash particles was ignorable under the conditions discussed in this paper. Experimental measurement results indicated that the accuracy of the thermographic temperature measurements improved significantly if the setting of the flame emissivity was adjusted according to the air/waste ratio. 相似文献
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The experiment in which a candle is burned inside an inverted vessel partially immersed in water has a history of more than
2,200 years, but even nowadays it is common that students and teachers relate the change in volume of the enclosed air to
its oxygen content. Contrary to what many people think, Lavoisier concluded that any change in volume in this experiment is
negligible; moreover, the explanation relating oxygen consumption in the air with its change in volume is known to be wrong.
In this work we briefly review the history behind the candle experiment and its relationship with some typical erroneous explanations.
One of the key factors behind Lavoisier’s success was the use of experiments carefully designed to test different hypotheses.
Following these steps, we performed several closed volume experiments where the candle wick was replaced by a capillary stainless
steel cylinder supported and heated by a nichrome filament connected to an external power supply. Our recorded experiments
are displayed as web pages, designed with the purpose that the reader can easily visualize and analyze modern versions of
Lavoisier’s experiments. These experiments clearly show an initial phase of complete combustion, followed by a phase of incomplete
combustion with elemental carbon or soot rising to the top of the vessel, and a final phase where the hot artificial wick
only evaporates a white steam of wax that cannot ignite because no oxygen is left in the closed atmosphere. After either a
complete or incomplete combustion of the oxygen, our experiments show that the final gas volume is nearly equal to the initial
air volume. 相似文献
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建立了热风炉栅格燃烧器内空、煤气流动混合过程的三维物理、数学模型,对燃烧器内流场特性和组分浓度均匀性进行了数值模拟。计算结果揭示了燃烧器内空、煤气流场结构及混合过程;得到了燃烧器空气和煤气通道的阻力系数、速度均匀度以及组分浓度均匀度;同时分析了冷风配气均匀度的影响因素,为热风炉燃烧特性的研究奠定了基础。 相似文献