This work is supported by an agreement with Syracuse University awarded by the Syracuse Center of Excellence in Energy and Environmental Systems with funding under prime award number DE-EE0006031 from the US Department of Energy and matching funding under award number 53367 from the New York State Energy Research and Development Authority (NYSERDA), contract 61736 from NYSERDA, and an award from Empire State Development's Division of Science, Technology and Innovation (NYSTAR) through the Syracuse Center of Excellence, under award number #C120183. This work is supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. 1247399.

1.燃烧计算<ol><li>分析选择的燃料。在这里，选择甲烷作为基准燃料，但原则是转移到其他烃类燃料。 </li><li>与1摩尔甲烷作为燃料，平衡公式（1）为化学计量燃烧来获得等式（2）。 <img alt="式（1）" src="/files/ftp_upload/54638/54638eq1.jpg" /> <img alt="公式（2）" src="/files/ftp_upload/54638/54638eq2.jpg" /></li><li>通过空气的质量除以甲烷的质量计算化学计算如等式3为甲烷燃烧的燃料-空气比（F / A 化学计量）。来计算，该分子是甲烷倍摩尔数甲烷的摩尔质量（16·G·摩尔-1），分母是氧倍摩尔的氧的摩尔质量数（32·G·摩尔-1）加的氮倍摩尔数氮的摩尔质量（28·G·摩尔-1）。 <img alt="公式3"SRC ="/文件/ ftp_upload / 54638 / 54638eq3.jpg"/&gt; </li><li>为了改变当量比（方程4），变化或者空气流量，燃料流量或同时两者。通常情况下，固定量之一并改变另一个。确定是否修复无论是对燃烧器的燃料或空气的流量。对于本实验，修正燃料流量在10升/分钟，并允许空气流速在此设置而变化。 <img alt="公式4" src="/files/ftp_upload/54638/54638eq4.jpg" /></li><li>随着燃料流速F，固定（10升/分），F / A 坚忍 。计算的（0.0583），并考虑到当量比的定义，计算出空气流量，一个，对于每个要测试的当量比。公式（5）提供了计算的气流速度在升/分的每个当量比的一个直接的方法和结果示为1的化学计量当量比。 <img alt="公式5" src="/files/ftp_upload/54638/54638eq5.jpg" /> 注:上FLAMM能力的限制（或爆炸上限）是最丰富的当量比即可以在不存在催化剂的骤冷火焰中燃烧。更高的当量比可以通过使用催化剂来获得，但仅非催化燃烧在本文中描述。查阅文献，评估选择的燃料燃烧上限。 </li></ol> 2.燃烧特性实验装置<ol><li>选择基于在步骤1.5中得到的流速为甲烷和空气质量流量控制器（微型燃料电池）。选择MFC大小时要小心，以确保MFC不会在其范围的低端测试期间（&lt;满刻度值的10％）运行。对于这个特定的情况下，使用40升/分和200升/分钟的MFC分别为甲烷和空气。 </li><li>通过铜管连接微型燃料电池的甲烷和空气罐。 </li><li>按照规定设置甲烷和空气罐为MFC适当的压力调节器由制造商。在这种情况下，将压力设置为138千帕（20磅）。 </li><li>校准微型燃料电池，以确保准确的流量。 </li><li>构造燃烧室。在这个实验中，制定了燃烧室914毫米长着168毫米出口直径。 <ol><li>钻头端口燃烧废气分析和沿着燃烧室的长度热电偶放置。所需的确切数目和间隔取决于火焰的尺寸和实验的目的。对于这种设置，第一空间5热电偶置于最靠近燃烧区域隔开7mm左右。空间的最后6热电偶除了14毫米。使用相同的间距排气口。 </li><li>经由端口孔插入的K型热电偶入燃烧室。对准热电偶尖端在燃烧室的中心。尺寸端口孔，以适应热电偶和高温金属套圈和螺母以防止泄漏密封。 </li></ol></li><li>康涅狄格州等的K型热电偶直接向数据采集模块。 </li><li>通过USB驱动器连接数据采集模块到计算机。 </li><li>燃料MFC的后立即和刚好在燃烧器之前附着在铜管路径的单向阀。定向阀，使流只能移动从MFC路程。该单向阀是一个重要的安全功能，以防止闪回。 </li><li>检查前后MFC设置有泄漏后铜管。使用用毛笔应用肥皂水管道检测泄漏的泄漏会产生气泡。 </li><li>通过铜管连接燃烧室和燃烧器的质量流量控制器。 </li><li>完成燃烧室设置后，选择测试排气口之一。连接该端口延伸到GC分析端口铜管。 </li><li>选择注射器从燃烧室拉排气然后将它推入GC进行分析。对于这个实验中，使用一个25毫升注射器。 </li><li>放置在与排气口连接到GC铜管线一个三通阀。双向阀的一端连接到GC中，第二到排气口和第三至25毫升注射器。铜管连接到三通阀。用注射器从室吸燃烧废气，然后将其推入GC进行分析。 </li><li>连接阀到GC和注射器3路。驱动注射器推杆，以确保手术成功。 注意:安装的简化示意图如图1所示。 </li></ol><img alt="图1" src="/files/ftp_upload/54638/54638fig1.jpg" /> 图1的燃烧特性的实验装置示意图。燃烧特性的实验装置示意图，显示燃料，空气和排气流量（黑色箭头）和数据流（红色箭头）。单向阀用于防止回火。 <aHREF ="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54638/54638fig1large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 3.燃烧特性试验<ol><li>在测试之前，推针筒柱塞在完全打开的排气口侧的三通阀。 </li><li>打开第一空气MFC到86.5升/分钟的流速。 </li><li>打开甲烷的MFC上的10升/分钟的流速。这产生1.10预混当量比，稍微富混合物，这是更容易点燃。 </li><li>打开热电偶上通过计算机模块，开始记录数据。 </li><li>用丁烷打火机点燃在燃烧室的端部的混合物。点火后，火焰应该在燃烧器前稳定。 </li><li>通过从86.5升/分钟的初始值调节空气的流速缓慢，以所需的值调整量比。小心不要太快移动或去flammab之外ility限制这将导致火焰熄灭。 </li><li>记录在数据文件中的温度读数温度稳定后，热电偶。 </li><li>再次，拉针筒柱塞以从排气口抽取燃烧废气。 </li><li>抽取燃烧废气后，打开阀门到GC侧三通和关闭排气口侧。 </li><li>推针筒柱塞，直到它完全关闭并且所有的排气的已发送到GC。 </li><li>直到所有连接端口到GC铜管的残余气体的去除重复步骤3.8-3.10。铜管的内部容积相比，注射器的体积将指示多少次的一个简单的分析步骤3.8-3.10需要重复。 </li><li>在油管删除所有剩余气体后提取用于分析的最终排气样。推废气入GC和转动的GC分析模式7,17。 </li><li>记录通过保存的数据GC在GC分析数据。 </li><li>直到所有想要当量比进行测试，重复步骤3.1-3.13。 </li></ol> 4.模型燃烧废气的发展<ol><li>画出燃烧废气种体积百分数来观察的趋势。 </li><li>确定模型燃烧废气截止浓度值。在开发初期MT-FFC分析模型燃烧废气的燃料，仅部件中出现显著比例（&gt; 1％）被包括在模型中的燃料。 </li><li>为模型的燃料仅选择产生在排气显著氢气和一氧化碳（每个组件&gt; 1％）的那些等价比率。 </li><li>记录每个排气组件会议4.3的标准的体积百分比。 </li></ol> 5.燃料电池测试设置<ol><li>确定流率范围为每种气体。乘以从用t的GC分析的结果所获得的体积百分比他总计每个燃料电池内所需的模型燃烧废气的流速。 </li><li>评估流速为每个燃烧排气物种的范围，以确定每个物种的最大和最小流量。 </li><li>根据在步骤2.1中描述的相同的原则选择流量计。 </li><li>通过经由铜管连接流量计的气罐构建测试装置。 </li><li>设置气体压力调节器，以用于流量计的规定值。 </li><li>放置的单向阀在使用可燃性气体的每个流量计下游的铜管路径。 </li><li>连接所有流量计出境口岸在一起，通过铜管和多方面的。 </li><li>上设置具有内部直径只比所述燃料电池的外部直径大的钢管内的微管式SOFC。密封燃料电池用陶瓷粘合剂的钢管。 </li><li>具有微管式SOFC的钢管连接到一块陶瓷耐火米aterial保持在炉中的燃料电池。 </li><li>利用与连接到微管式SOFC用在阳极2线和阴极2线的电流收集和电压感测线的4探针技术10,11。确保线不会相互交叉创建短裤。 </li><li>把四根导线连接到恒电位仪10,11的四个探头。 </li><li>稳压器连接到计算机10,11。 </li><li>放置一个热电偶在与尖端接触微管式SOFC电解质10,11的外部的炉中。 </li><li>附加热电偶线到数据采集模块。 </li><li>通过USB端口连接数据采集模块到计算机。 注: 图2是示出了MT-FFC测试设置的简化示意图。与开发的模型的燃料和用于控制模型燃料流至燃料电池建立的设置，测试可根据常规˚F继续UEL电池测试方法。这些方法是公建立在文献中和在此将不再重复。 </li></ol><img alt="图2" src="/files/ftp_upload/54638/54638fig2.jpg" /> 的H 2，CO，CO 2 图2微管状火焰辅助燃料电池测试设置示意图。流动N 2（黑色箭头）与一个MFC和一个单向阀，以防止回火调节。从SOFC在炉内的电子流（绿线）的电位和回向SOFC。热电偶数据和电化学数据流由红色箭头表示。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54638/54638fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

<ol>
	<li>Gorte, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+developments+towards+commercialization+of+solid+oxide+fuel+cells.">Recent developments towards commercialization of solid oxide fuel cells.</a> AIChE J. 51 (9), 2377-2381 (2005).</li><li>Milcarek, R. J., Wang, K., Falkenstein-Smith, R. L., Ahn, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Micro-tubular+flame-assisted+fuel+cells+for+micro-combined+heat+and+power+systems.">Micro-tubular flame-assisted fuel cells for micro-combined heat and power systems.</a> J. Power Sources. 306, 148-151 (2016).</li><li>Horiuchi, M., Suganuma, S., Watanabe, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemical+power+generation+directly+from+combustion+flame+of+gases,+liquids,+and+solids.">Electrochemical power generation directly from combustion flame of gases, liquids, and solids.</a> J. Electrochem. Soc. 151 (9), A1402-A1405 (2004).</li><li>Starik, A. M., Kuleshov, P. S., Loukhovitski, B. I., Titova, N. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Theoretical+study+of+partial+oxidation+of+methane+by+non-equilibrium+oxygen+plasma+to+produce+hydrogen+rich+syngas.">Theoretical study of partial oxidation of methane by non-equilibrium oxygen plasma to produce hydrogen rich syngas.</a> Int. J. Hydrogen Energy. 40 (32), 9872-9884 (2015).</li><li>Katta, V. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+flames+established+with+jet+in+cross+flow+of+fuel-rich+combustion.">On flames established with jet in cross flow of fuel-rich combustion.</a> Fuel. 150, 360-369 (2015).</li><li>Maruta, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extinction+limits+of+catalytic+combustion+in+microchannels.">Extinction limits of catalytic combustion in microchannels.</a> P. Combustion Institute. 29 (1), 957-963 (2002).</li><li>Ahn, J., Eastwood, C., Sitzki, L., Ronney, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gas-phase+and+catalytic+combustion+in+heat-recirculating+burners.">Gas-phase and catalytic combustion in heat-recirculating burners.</a> P. Combustion Institute. 30 (2), 2463-2472 (2005).</li><li>K&#1255;hler, M., O&#223;wald, P., Xu, H., Kathrotia, T., Hasse, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Speciation+data+for+fuel-rich+methane+oxy-combustion+and+reforming+under+prototypical+partial+oxidation+conditions.">Speciation data for fuel-rich methane oxy-combustion and reforming under prototypical partial oxidation conditions.</a> Chemical Engineering Science. 139, 249-260 (2016).</li><li>Ahn, J., Ronney, P. D., Shao, Z., Haile, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+thermally+self-sustaining+miniature+solid+oxide+fuel+cell.">A thermally self-sustaining miniature solid oxide fuel cell.</a> J. Fuel Cell Science and Technology. 6 (4), 041004 (2009).</li><li>Wang, K., Milcarek, R. J., Zeng, P., Ahn, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flame-assisted+fuel+cells+running+methane.">Flame-assisted fuel cells running methane.</a> Int. J. Hydrogen Energy. 40 (13), 4659-4665 (2015).</li><li>Wang, K., Zeng, P., Ahn, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+performance+direct+flame+fuel+cell+using+a+propane+flame.">High performance direct flame fuel cell using a propane flame.</a> P. Combust. Inst. 32 (2), 3431-3437 (2011).</li><li>Wang, Y. Q., Shi, Y. X., Yu, X. K., Cai, N. S., Li, S. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integration+of+solid+oxide+fuel+cells+with+multi-element+diffusion+flame+burners.">Integration of solid oxide fuel cells with multi-element diffusion flame burners.</a> J. Electochem. Soc. 160 (11), F1241-F1244 (2013).</li><li>Horiuchi, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Performance+of+a+solid+oxide+fuel+cell+couple+operated+via+in+situ+catalytic+partial+oxidation+of+n-butane.">Performance of a solid oxide fuel cell couple operated via in situ catalytic partial oxidation of n-butane.</a> J. Power Sources. 189 (2), 950-957 (2009).</li><li>Wang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+study+of+portable+direct-flame+solid+oxide+fuel+cell+(DF-SOFC)+stack+with+butane+fuel.">The study of portable direct-flame solid oxide fuel cell (DF-SOFC) stack with butane fuel.</a> J. Fuel Chem. Technol. 42 (9), 1135-1139 (2014).</li><li>Wang, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+high-performance+no-chamber+fuel+cell+operated+on+ethanol+flame.">A high-performance no-chamber fuel cell operated on ethanol flame.</a> J. Power Sources. 177 (1), 33-39 (2008).</li><li>Sun, L., Hao, Y., Zhang, C., Ran, R., Shao, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coking-free+direct-methanol-flame+fuel+cell+with+traditional+nickel-cermet+anode.">Coking-free direct-methanol-flame fuel cell with traditional nickel-cermet anode.</a> Int. J. Hydrogen Energy. 35 (15), 7971-7981 (2010).</li><li>Zeng, P., Wang, K., Falkenstein-Smith, R. L., Ahn, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+sintering+temperature+on+the+performance+of+SrSc0.1Co0.9O3-&#948;+oxygen+semipermeable+membrane.">Effects of sintering temperature on the performance of SrSc0.1Co0.9O3-&#948; oxygen semipermeable membrane.</a> Braz. J. Chem. Eng. 32 (3), 757-765 (2015).</li><li>Turns, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An Introduction to Combustion: Concepts and Applications. , (2000).</li><li>Glassman, I., Yetter, R. A., Glumac, N. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Combustion. , (2015).</li></ol>

The authors have nothing to disclose.

这里讨论的协议是以往的燃烧特性的研究和燃料电池测试之间的重要桥梁。燃料重整和燃料电池测试使用燃烧的已DFFC设置10-15已应用数年。然而，在DFFCs燃烧过程的表征主要涉及原位火焰组合物16的特性，并使用MS 8。作为DFFC是开放的环境中，排气组合物由主要是水和CO 2，而不是所需要的排气的表征。为了开发最近FFC概念的过程用于在部分封闭的腔室表征燃烧排气（ 即 ，一个保持燃料-空气比）是必要的。代替使用的MS的，为GC是适用于燃烧废气分析7。表征排气，一个简单的方法为这个EXH内测试燃料电池后AUST是必要的。虽然这是可能开发的完全集成的燃烧器和燃料电池测试装置中，该过程提供了可应用于具有不同排气组合物中的燃料电池的性能的科学调查的简单初始步骤。虽然燃烧特性的方法是常见的，其FFC研究应用是一个重要的发展。 在此过程中的最重要的步骤是确保适当的安全防范措施之前，点火服用;并确保没有空气漏入燃烧室。使用单向阀和/或阻火以及耐高温材料是用于该装置和研究人员的安全性非常重要。如结果部分中所示，如果有回流量或空气的其它泄漏到燃烧室可​​发生大范围的不正确的结果。此逆流改变混合物的当量比，并且可以产生不同的混合创造像图3中所示的结果的模式。 而两种方法用于确定是否有空气的逆流到燃烧室已经描述，有确定这是发生的第三方式。如果火焰持续时用于空气在MFC被关闭，以燃烧该方法简单地评估。在此预混合燃烧过程中燃烧反应的唯一空气通过MFC提供。点火后，空气供应可以在燃料被留在被关闭。火焰将在没有空气的熄灭。如果燃烧继续，则逆流空气进入燃烧室正在发生。确定后有空气的逆流到燃烧室，以防止空气的逆流的必要，然后再继续。解决了这个问题可以相对简单。燃烧废气是热的，因此不太活跃，这导致它上升到燃烧的顶部室。空气的任何逆流进入腔室端将发生在室的底部。阻塞燃烧室排气口的底部后，上述可再次执行的三种技术，以确保没有空气被回流入室中。这个讨论假设室已经被检查是否有泄漏。完全混合还应通过确保检测到的任何甲烷是在痕量和GC测量是可重复的验证。 表征燃烧排气和开发模型燃烧废气组合物后，有一个范围的用于燃料电池的测试应用。该协议部分介绍此技术的微管式SOFC测试的具体应用。然而，同样的基本过程可以应用于用于测试其它燃料电池的几何形状，包括平面的，以及较大的管状固体氧化物燃料电池。该协议还延伸到测试堆设计的任一几何形状。此外的协议并不限于甲烷作为燃料。该方法可以扩展到其它的烷烃和醇燃料也具有从富燃料燃烧过程用于产生的H 2和CO显著潜力。 而描述的协议有许多应用进一步FFCS的发展，也有该技术的局限性。该协议已经建立，以测试在不同的富燃料燃烧过程和燃料运行SOFC中的可能性。当燃料电池模型富燃料废气操作是观察的潜力。具体而言，有前途的性能的关键指标包括高功率密度，电流密度，燃料利用率和所述燃料电池实现开路电压。然而，只有存在的最显著物种模型燃料的发展限制可以进行的研究。例如，在模型燃烧废气进行长期测试操作固体氧化物燃料电池是可能的，但我t可以不提供的燃料电池的实际长期性能特性的最佳指示。从长远来看，有的在燃烧废气的微量物质可能会成为有损于固体氧化物燃料电池的性能。测试这些结果需要充分整合SOFC的与实际燃烧器和完整的燃烧废气。而这些限制都存在，该技术仍然提供了评估FFCS性能和势作为发电的未来来源的简单和控制的装置。

固体氧化物燃料电池（SOFC）的革新已报道在近年来随着技术的不断发展。在众多的优势，固体氧化物燃料电池已经成为众所周知的高燃油效率，低排放和燃油适中灵活性相对于其他基于燃发电技术1。此外，固体氧化物燃料电池是可伸缩的，可用于高燃油效率，即使在小尺度。不幸的是，在当前的氢基础设施的限制已经创建需要一种通常低效的燃料重整系统。最近的发展是微型管状火焰辅助燃料电池（MT-FFC）在笔者的前期工作2的报道。所述MT-FFC是建立在原有的火焰直接型燃料电池（DFFC），其提供热量和燃料通过燃烧3重整的好处的火焰辅助燃料电池（FFC）的第一个例子。该DFFC设置放在与火焰直接接触到开放环境ENVIR一个SOFConment。火焰的部分氧化较重烃类燃料来创建的 H 2和CO，它可以直接用较少潜在相比纯甲烷或其它较重的烃可以使用在固体氧化物燃料电池为碳焦化。另外，该火焰提供以使固体氧化物燃料电池，以它的工作温度所需要的热能。原来的DFFC最近发生的变化通过移动SOFC出火焰区和窜燃烧废气的SOFC创建FFC 2。不像DFFC，燃烧发生在一个部分封闭的腔室（而不是环境温度），以便可以控制燃料与空气的比值和排气，可直接供给到燃料电池不完全燃烧的发生。 FFCS具有其他优势，包括高燃料利用率和电机效率高相比DFFCs 2。 作为一个新兴的研究领域，需要的实验技术，可以评估MT-FF的潜力CS为未来的发电应用。这些技术需要部分氧化，或富燃料燃烧，并已被鉴定为产生的 H 2和CO，也被称为合成气的一种方式的排气分析，用CO 2和H 2 O沿合成气可以直接在燃料电池发电中使用。富燃料燃烧废气的分析已经很好地建立在近年来已进行了理论上4，计算5,6-和实验7用于许多不同的目的。许多理论和计算研究都依赖于化学平衡分析（CEA），以评估燃烧产物品种是积极有利的，和化学动力学模型反应机理。虽然这些方法非常有用，许多新兴技术都在实验技术的研究和开发过程中依赖。实验技术通常依赖于ANA利用燃烧废气的裂解任一气体色谱仪（GC）7或质谱仪（MS）8。无论在GC线/注射器或MS探针插入燃烧废气和测量以评估物种的浓度。实验技术的应用在小规模发电的区域已经屡见不鲜。一些实例包括已开发了单室固体氧化物燃料电池7,9和DFFCs 10-15操作微燃烧器。在宽范围的操作条件，包括不同的温度，流速和当量比发生燃烧废气的分析。 在DFFC研究，燃料和氧化剂的区域可以是部分预混合或非预混，与燃烧器开放以保证完全燃烧的环境。与需要分析火焰组合物中，MS已经在许多情况下用于DFFC研究和燃烧分析16。的FFC的最近发展通过在部分封闭的环境依靠预混合燃烧与燃烧器，以防止燃料的完全氧化而不同。其结果是，需要在从漏气自由受控环境燃烧废气的分析。为此目的开发的实验技术依赖于用于微燃烧室研究与在不同当量比的燃烧排气的GC分析较早的技术。 GC分析导致燃烧废气组合物的表征（ 即 ，每个排气组分包括二氧化碳的体积％，H 2 O，N 2 等 ）该分析允许根据由测得的比率分离气体的混合GC创造未来FFC研究的典范富燃料燃烧废气。 分析富燃料燃烧废气，发展模式富燃料燃烧废气和应用协议ING的SOFC测试排气建立在本文中。共同的挑战和限制对这些技术进行讨论。

<table><tbody><tr><td>Gas chromotograph</td><td>SRI Instruments, Inc.</td><td>SRI 8610C</td><td></td></tr><tr><td>K type thermocouples</td><td>Omega</td><td>KQXL-116G-6</td><td>Custom length</td></tr><tr><td>K type thermocouple extension wire</td><td>Omega</td><td>EXTT-K-20-SLE-100</td><td></td></tr><tr><td>Mass flow controller</td><td>Omega</td><td>FMA5427</td><td>0-40 L/min (N&lt;sub&gt;2&lt;/sub&gt;)&lt;br/&gt; Used for methane</td></tr><tr><td>Mass flow controller</td><td>Omega</td><td>FMA5443</td><td>0-200 L/min (N&lt;sub&gt;2&lt;/sub&gt;)&lt;br/&gt; Used for air</td></tr><tr><td>Mass flow controller</td><td>Omega</td><td>FMA5402A</td><td>0-10 ml/min (N&lt;sub&gt;2&lt;/sub&gt;)&lt;br/&gt; Used for CO</td></tr><tr><td>Mass flow controller</td><td>Brooks Instrument</td><td>SLA5850</td><td>200 SCCM (Propane)&lt;br/&gt; Used for CO&lt;sub&gt;2&lt;/sub&gt;</td></tr><tr><td>Mass flow controller</td><td>Brooks Instrument</td><td>SLA5850</td><td>5 L/min (Air)&lt;br/&gt; Used for N&lt;sub&gt;2&lt;/sub&gt;</td></tr><tr><td>Mass flow controller</td><td>Brooks Instrument</td><td>SLA5850</td><td>500 SCCM (N&lt;sub&gt;2&lt;/sub&gt;)&lt;br/&gt; Used for H&lt;sub&gt;2&lt;/sub&gt;</td></tr><tr><td>Regulator</td><td>Harris Products Group</td><td>HP721-125-350-F</td><td>Methane tank</td></tr><tr><td>Regulator</td><td>Harris Products Group</td><td>HP702-050-590-E</td><td>Air tank</td></tr><tr><td>Regulator</td><td>Airgas</td><td>Y11-SR145B</td><td>CO tank</td></tr><tr><td>Regulator</td><td>Harris Products Group</td><td>HP702-050-320-E</td><td>CO&lt;sub&gt;2&lt;/sub&gt; tank</td></tr><tr><td>Regulator</td><td>Airgas</td><td>Y12-215B</td><td>N&lt;sub&gt;2&lt;/sub&gt; tank</td></tr><tr><td>Regulator</td><td>Harris Products Group</td><td>HP702-015-350-D</td><td>H&lt;sub&gt;2&lt;/sub&gt; tank</td></tr><tr><td>Methane, Compressed,&lt;br/&gt;Ultra high purity</td><td>Airgas</td><td>UN1971</td><td>Extremely Flammable</td></tr><tr><td>Air, Compressed,&lt;br/&gt;Ultra pure</td><td>Airgas</td><td>UN1002</td><td>Not classified as hazardous to health.</td></tr><tr><td>CO, Compressed,&lt;br/&gt;Ultra high purity</td><td>Airgas</td><td>UN1016</td><td>Toxic by inhalation, Extremely flammable</td></tr><tr><td>CO&lt;sub&gt;2&lt;/sub&gt;, Compressed,&lt;br/&gt;Research grade</td><td>Airgas</td><td>UN1013</td><td>Asphyxiant in high concentrations</td></tr><tr><td>N&lt;sub&gt;2&lt;/sub&gt;, Compressed,&lt;br/&gt; Ultra high purity</td><td>Airgas</td><td>UN1066</td><td>Not classified as hazardous to health.</td></tr><tr><td>H&lt;sub&gt;2&lt;/sub&gt;, Compressed,&lt;br/&gt; Ultra high purity</td><td>Airgas</td><td>UN1049</td><td>Extremely flammable, burns with invisible flame</td></tr><tr><td>Source meter</td><td>Tektronix, Inc.</td><td>Keithley 2420</td><td>Connects to computer via USB</td></tr><tr><td>Horizontal split tube furnace</td><td>MTI Corportation</td><td>OTF-1200X</td><td></td></tr><tr><td>Data acquisition</td><td>National Instruments</td><td>NI cDAQ-9172</td><td>Connects to computer via USB</td></tr><tr><td>Thermocouple input</td><td>National Instruments</td><td>NI 9211</td><td>Connects to cDAQ-9172</td></tr><tr><td>Computer control for Mass Flow Controllers</td><td>National Instruments</td><td>NI 9263</td><td>Connects to cDAQ-9172&lt;br/&gt; Computer control for Mass Flow Controllers</td></tr><tr><td>Testing software</td><td>National Instruments</td><td>LabVIEW 8.6</td><td></td></tr><tr><td>Ceramabond</td><td>Aremco</td><td>552-VFG</td><td>1 Pint</td></tr></tbody></table>

combustion characterization and model fuel development for micro-tubular flame-assisted fuel cells

Combustion based power generation has been accomplished for many years through a number of heat engine systems. Recently, a move towards small scale power generation and micro combustion as well as development in fuel cell research has created new means of power generation that combine solid oxide fuel cells with open flames and combustion exhaust. Instead of relying upon the heat of combustion, these solid oxide fuel cell systems rely on reforming of the fuel via combustion to generate syngas for electrochemical power generation. Procedures were developed to assess the combustion by-products under a wide range of conditions. While theoretical and computational procedures have been developed for assessing fuel-rich combustion exhaust in these applications, experimental techniques have also emerged. The experimental procedures often rely upon a gas chromatograph or mass spectrometer analysis of the flame and exhaust to assess the combustion process as a fuel reformer and means of heat generation. The experimental techniques developed in these areas have been applied anew for the development of the micro-tubular flame-assisted fuel cell. The protocol discussed in this work builds on past techniques to specify a procedure for characterizing fuel-rich combustion exhaust and developing a model fuel-rich combustion exhaust for use in flame-assisted fuel cell testing. The development of the procedure and its applications and limitations are discussed.

燃烧特性室应当在期望当量比为空气的逆流进入测试期间的腔室或其他空气泄漏测试之前进行检查。在开室燃烧过程被称为是几乎同量异序。其结果是，燃烧室内的压力可能不足以确保无来自外部环境的空气是回流入从室排气口或其它渗漏点燃烧室。有几个实验技术，以确认没有逆流发生。首先，对于一个非催化燃烧器，富-可燃性限值是公建立了许多燃料18,19。点火之后，流程的当量比应缓慢，直到它接近富自燃极限的调整。如果富人的可燃极限可以显著没有熄火被突破，则有证据表明，空气倒流入T他导致比所希望的更瘦混合物燃烧室。 图3示出了用于干甲烷燃烧废气达1.85当量比得到初步结果。尽管图3中未显示，火焰没有淬火高达3.97当量比。仅为1.64报道18丰富可燃性极限，获得的3.97当量比是不可能与非催化燃烧。这些结果表明，有空气泄漏到燃烧室和一个可能的来源是从排气出口回流。 <img alt="图3" src="/files/ftp_upload/54638/54638fig3.jpg" /> 之前防止空气倒流到燃烧室节目种类的随机波动。图3. 初始燃烧排气表征。分析结果。与预期的偏差趋势既表明搭配不当ING或空气泄漏。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54638/54638fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 的可燃性燃烧室的上限考试是不检查回流的唯一途径。从图3中的第二指示是几个排气物种的趋势不遵循预期的趋势。 CEA是用于评估在其上的产品是温度，压力，和当量比的不同条件下积极有利的基于燃烧产物的常用技术。 CEA提供了评估趋势应该是在这个实验中观察到的一种方式。不同的CEA结果为普通燃料可以在文献中找到，或者可以使用用于此任务开发的软件程序来评估。 图4显示了CEA的结果为在无水甲烷combusti主物种<html>在排气管。而在图3偏离所示从预期的趋势几乎所有排气物种，O 2可能是最重要的。在当量比大于1时，非常少的 O 2，预计作为大部分应该燃烧期间被消耗以形成燃烧产物。同时将O 2浓度在大多数的范围的低，在相比降低当量比为1.75和1.85当量比获得更高量的 O 2不期望。这可能是不完全混合或O 2的回流到燃烧室的一个可能的指示。此外，检测在这个范围内以1％（体积）或更高的 CH 4也是不完全混合的可能指示。通过使用CEA的结果进行比较的趋势分析可用于指示是否有空气或可能的混合问题的回流。 p_upload / 54638 / 54638fig4.jpg"/&gt; 图4. 燃烧甲烷/空气化工产品均衡分析化学平衡分析（CEA）结果表明，在不同的当量比废气成分热力学平衡的预测。尽管实验数据不完全匹配，CEA提供的预期趋势的指示。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54638/54638fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 检测在燃烧室排气的回流量和通过如在讨论部分所述阻断所述燃烧室排气口的部分防止。阻塞燃烧室排气口的一部分后的富自燃极限具有大约1.45的燃烧室的当量比。与逆流防止燃烧排气在表1中示出的当量比和燃料和空气流速进行评估。在使用等式5 所示 。 图5中的协议的步骤1.5获得表1中所示的流速分别示出了干燃烧排气表征为结果在表中所示的条件1。 图5证实了实际的趋势是可比图4中所示的CEA的结果。这提供了结果的一些验证。然而，也有一些点，从CEA趋势如CO 2在1.45当量比偏离。在1.45当量比的误差的一部分是，燃烧器附近的富自燃极限，这可能会导致在排气样品中的火焰，可能淬火和偏差内不稳定运行。分析应重复以确保结果的重复性和准确度。操作丰富-FL下方建议室（ 例如，围绕在此设置的1.4最大的当量比）的可燃性极限。 <table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td> 当量比 </td><td> 甲烷流量（升/分钟） </td><td> 空气流量（升/分钟） </td></tr><tr><td> 0.80 </td><td> 10 </td><td> 119.0 </td></tr><tr><td> 0.90 </td><td> 10 </td><td> 105.8 </td></tr><tr><td> 1.00 </td><td> 10 </td><td> 95.0 </td></tr><tr><td> 1.05 </td><td> 10 </td><td> 90.6 </td></tr><tr><td> 1.10 </td><td> 10 </td><td> 86.5 </td></tr><tr><td> 1.15 </td><td> 10 </td><td> 82.8 </td></tr><tr><td> 1.20 </td><td> 10 </td><td> 79.3 </td></tr><tr><td> 1.25 </td><td> 10 </td><td> 76.1 </td></tr><tr><td> 1.30 </td><td> 10 </td><td> 73.2 </td></tr><tr><td> 1.35 </td><tD&gt; 10 </td><td> 70.5 </td></tr><tr><td> 1.40 </td><td> 10 </td><td> 68.0 </td></tr><tr><td> 1.45 </td><td> 10 </td><td> 65.7 </td></tr></tbody></table> 表1.燃烧表征甲烷和空气流速以变化的等值比率。所需流率的计算是在协议的第1节中讨论。方程5来计算基于所述当量比，并固定甲烷流速的空气流率。 <img alt="图5" src="/files/ftp_upload/54638/54638fig5.jpg" /> 从甲烷/空气燃烧排气 图5. 燃烧表征分析。防止空气倒流到燃烧室之后获得改进的结果。的趋势是相似的CEA的预测提供了结果的准确性的信心。多个测试当从预期的趋势出现偏差，可能需要在排气。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54638/54638fig5large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 随着燃烧废气特征值最高达富可燃性极限，模型燃烧废气能为MT-FFC测试开发。模型燃烧废气的发展取决于其排气物种是最相关的研究。在FFCS的最​​初研究中，主要关心的是在使用可电化学能量转换相对少量的燃料的理解在燃烧排气中的燃料电池的性能特性。这些特征包括峰值功率密度，电流密度，开路电压，燃料利用率和在不同的当量比效率和工作温度。在一个相对较小的燃料浓度工作为o的该区分FFCS尽可能多的燃料电池具有高浓度的燃料和低浓度的其它气体包括CO 2，H 2 O和除其他惰性气体的操作的主要功能的网元。为了使这个评估仅在燃烧特性与体积百分比检测气体高于1％被包含在模型燃烧废气。其结果是，只有H 2，CO，CO 2和N 2分别需要开发为甲烷燃烧模型富燃料燃烧废气。 表2示出了燃烧特性评估的结果。对300毫升/分钟的燃料电池的阳极侧的总流量，每个品种的流率也列于表2中。 <table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td> 当量比 </td><td> H 2体积％ </td><td> H <sub&gt; 2（毫升·分钟-1） </td><td> CO体积％ </td><td> CO（毫升·分钟-1） </td><td> 的 CO 2体积％ </td><td> 二氧化碳 （毫升·分钟-1） </td><td> N 2体积％ </td><td> N 2（毫升·分钟-1） </td><td> 总（毫升·分钟-1） </td></tr><tr><td> 1.10 </td><td> 1.1 </td><td> 3.2 </td><td> 2.4 </td><td> 7.2 </td><td> 11.3 </td><td> 34.0 </td><td> 85.2 </td><td> 255.6 </td><td> 300 </td></tr><tr><td> 1.15 </td><td> 1.8 </td><td> 5.4 </td><td> 3.2 </td><td> 9.7 </td><td> 10.6 </td><td> 31.9 </td><td> 84.4 </td><td> 253.1 </td><td> 300 </td></tr><tr><td> 1.20 </td><td> 4.3 </td><td> 12.9 </td><td> 4.6 </td><td> 13.8 </td><td> 10.0 </td><td> 29.9 </td><td> 81.1 </td><td> 243.4 </td><td> 300 </tD&gt; </tr><tr><td> 1.25 </td><td> 6.4 </td><td> 19.1 </td><td> 5.6 </td><td> 16.7 </td><td> 9.2 </td><td> 27.6 </td><td> 78.9 </td><td> 236.6 </td><td> 300 </td></tr><tr><td> 1.30 </td><td> 8 </td><td> 24.0 </td><td> 6.5 </td><td> 19.5 </td><td> 8.5 </td><td> 25.6 </td><td> 77.0 </td><td> 230.9 </td><td> 300 </td></tr><tr><td> 1.35 </td><td> 11.5 </td><td> 34.6 </td><td> 8 </td><td> 24.1 </td><td> 8.3 </td><td> 24.8 </td><td> 72.2 </td><td> 216.5 </td><td> 300 </td></tr><tr><td> 1.40 </td><td> 12.4 </td><td> 37.3 </td><td> 8.7 </td><td> 26.2 </td><td> 7.6 </td><td> 22.7 </td><td> 71.3 </td><td> 213.8 </td><td> 300 </td></tr></tbody></table>为燃烧特性得到表2中 模型燃烧废气的组成和流速。实验结果显示为体积p检测到的物种ercents。用于燃料电池模型富燃料燃烧废气的总流速设定为300毫升/分。每个单独的物种的流量是由总流量和每一个物种的体积百分数乘以。

Watch this Scientific Journal Video about Combustion Characterization and Model Fuel Development for Micro-tubular Flame-assisted Fuel Cells at JoVE.com

Combustion Characterization and Model Fuel Development for Micro-tubular Flame-assisted Fuel Cells

A protocol for creating a model fuel-rich combustion exhaust is developed through combustion characterization and is applied for micro-tubular flame-assisted fuel cell testing and research.

燃烧特性参数和模型燃料开发的微型管状火焰辅助燃料电池

Combustion based power generation has been accomplished for many years through a number of heat engine systems. Recently, a move towards small scale power ...

combustion-characterization-model-fuel-development-for-micro-tubular

Nanyang Technological University

Research

Education

JoVE Journal

JoVE Core

Organic Chemistry

Engineering

Unit 1

Alkanes and Cycloalkanes

SCIENTISTS IN ACTION

9.5K 次观看.  Syracuse University. A protocol for creating a model fuel-rich combustion exhaust is developed through combustion characterization and is applied for micro-tubular flame-assisted fuel cell testing and research.

视频: Combustion Characterization and Model Fuel Development for Micro-tubular Flame-assisted Fuel Cells

Probing and Mapping Electrode Surfaces in Solid Oxide Fuel Cells

Solid oxide fuel cells (SOFCs) are potentially the most efficient and cost-effective solution to utilization of a wide variety of fuels beyond hydrogen 1-7. The performance of SOFCs and the rates of many chemical and energy transformation processes in energy storage and conversion devices in general are limited primarily by charge and mass transfer along electrode surfaces and across interfaces. Unfortunately, the mechanistic understanding of these processes is still lacking, due largely to the difficulty of characterizing these processes under in situ conditions. This knowledge gap is a chief obstacle to SOFC commercialization. The development of tools for probing and mapping surface chemistries relevant to electrode reactions is vital to unraveling the mechanisms of surface processes and to achieving rational design of new electrode materials for more efficient energy storage and conversion2. Among the relatively few in situ surface analysis methods, Raman spectroscopy can be performed even with high temperatures and harsh atmospheres, making it ideal for characterizing chemical processes relevant to SOFC anode performance and degradation8-12. It can also be used alongside electrochemical measurements, potentially allowing direct correlation of electrochemistry to surface chemistry in an operating cell. Proper in situ Raman mapping measurements would be useful for pin-pointing important anode reaction mechanisms because of its sensitivity to the relevant species, including anode performance degradation through carbon deposition8, 10, 13, 14 ("coking") and sulfur poisoning11, 15 and the manner in which surface modifications stave off this degradation16. The current work demonstrates significant progress towards this capability. In addition, the family of scanning probe microscopy (SPM) techniques provides a special approach to interrogate the electrode surface with nanoscale resolution. Besides the surface topography that is routinely collected by AFM and STM, other properties such as local electronic states, ion diffusion coefficient and surface potential can also be investigated17-22. In this work, electrochemical measurements, Raman spectroscopy, and SPM were used in conjunction with a novel test electrode platform that consists of a Ni mesh electrode embedded in an yttria-stabilized zirconia (YSZ) electrolyte. Cell performance testing and impedance spectroscopy under fuel containing H2S was characterized, and Raman mapping was used to further elucidate the nature of sulfur poisoning. In situ Raman monitoring was used to investigate coking behavior. Finally, atomic force microscopy (AFM) and electrostatic force microscopy (EFM) were used to further visualize carbon deposition on the nanoscale. From this research, we desire to produce a more complete picture of the SOFC anode.

We present a unique platform for characterizing electrode surfaces in solid oxide fuel cells (SOFCs) that allows simultaneous performance of multiple characterization techniques (e.g. in situ Raman spectroscopy and scanning probe microscopy alongside electrochemical measurements). Complementary information from these analyses may help to advance toward a more profound understanding of electrode reaction and degradation mechanisms, providing insights into rational design of better materials for SOFCs.

在固体氧化物燃料电池电极表面的探测和测绘

Solid oxide fuel cells (SOFCs) are potentially the most efficient and cost-effective solution to utilization of a wide variety of fuels beyond hydrogen ...

科研

工程学

Flame Experiments at the Advanced Light Source: New Insights into Soot Formation Processes

The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory1-4. This video demonstrates how the complex chemical structures of laboratory-based model flames are analyzed using flame-sampling mass spectrometry with tunable synchrotron-generated vacuum-ultraviolet (VUV) radiation. This experimental approach combines isomer-resolving capabilities with high sensitivity and a large dynamic range5,6. The first part of the video describes experiments involving burner-stabilized, reduced-pressure (20-80 mbar) laminar premixed flames. A small hydrocarbon fuel was used for the selected flame to demonstrate the general experimental approach. It is shown how species&#8217; profiles are acquired as a function of distance from the burner surface and how the tunability of the VUV photon energy is used advantageously to identify many combustion intermediates based on their ionization energies. For example, this technique has been used to study gas-phase aspects of the soot-formation processes, and the video shows how the resonance-stabilized radicals, such as C3H3, C3H5, and i-C4H5, are identified as important intermediates7. The work has been focused on soot formation processes, and, from the chemical point of view, this process is very intriguing because chemical structures containing millions of carbon atoms are assembled from a fuel molecule possessing only a few carbon atoms in just milliseconds. The second part of the video highlights a new experiment, in which an opposed-flow diffusion flame and synchrotron-based aerosol mass spectrometry are used to study the chemical composition of the combustion-generated soot particles4. The experimental results indicate that the widely accepted H-abstraction-C2H2-addition (HACA) mechanism is not the sole molecular growth process responsible for the formation of the observed large polycyclic aromatic hydrocarbons (PAHs).

Gas sampling from laboratory-scale flames with online analysis of all species by mass spectrometry is a powerful method to investigate the complex mixture of chemical compounds occurring during combustion processes. Coupled with tunable soft ionization via synchrotron-generated vacuum-ultraviolet radiation, this technique provides isomer-resolved information and potentially fragment-free mass spectra.

火焰在实验的先进光源：全新洞察烟灰形成过程

The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics ...

Preparation and Evaluation of Hybrid Composites of Chemical Fuel and Multi-walled Carbon Nanotubes in the Study of Thermopower Waves

When a chemical fuel at a certain position in a hybrid composite of the fuel and a micro/nanostructured material is ignited, chemical combustion occurs along the interface between the fuel and core materials. Simultaneously, dynamic changes in thermal and chemical potentials across the micro/nanostructured materials result in concomitant electrical energy generation induced by charge transfer in the form of a high-output voltage pulse. We demonstrate the entire procedure of a thermopower wave experiment, from synthesis to evaluation. Thermal chemical vapor deposition and the wet impregnation process are respectively employed for the synthesis of a multi-walled carbon nanotube array and a hybrid composite of picric acid/sodium azide/multi-walled carbon nanotubes. The prepared hybrid composites are used to fabricate a thermopower wave generator with connecting electrodes. The combustion of the hybrid composite is initiated by laser heating or Joule-heating, and the corresponding combustion propagation, direct electrical energy generation, and real-time temperature changes are measured using a high-speed microscopy system, an oscilloscope, and an optical pyrometer, respectively. Furthermore, the crucial strategies to be adopted in the synthesis of hybrid composite and initiation of their combustion that enhance the overall thermopower wave energy transfer are proposed.

A protocol for conducting thermopower wave experiments is presented. The synthesis of hybrid composites of a chemical fuel and micro/nanostructured material, manufacturing of a thermopower wave generator, and methods for measuring the corresponding physical phenomena are described.

化学燃料和多壁碳纳米管的混杂复合材料的热电波的研究准备和评估

When a chemical fuel at a certain position in a hybrid composite of the fuel and a micro/nanostructured material is ignited, chemical combustion occurs ...

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model

Analysis of the size distribution of nanocrystals is a critical requirement for the processing and optimization of their size-dependent properties. The common techniques used for the size analysis are transmission electron microscopy (TEM), X-ray diffraction (XRD) and photoluminescence spectroscopy (PL). These techniques, however, are not suitable for analyzing the nanocrystal size distribution in a fast, non-destructive and a reliable manner at the same time. Our aim in this work is to demonstrate that size distribution of semiconductor nanocrystals that are subject to size-dependent phonon confinement effects, can be quantitatively estimated in a non-destructive, fast and reliable manner using Raman spectroscopy. Moreover, mixed size distributions can be separately probed, and their respective volumetric ratios can be estimated using this technique. In order to analyze the size distribution, we have formulized an analytical expression of one-particle PCM and projected it onto a generic distribution function that will represent the size distribution of analyzed nanocrystal. As a model experiment, we have analyzed the size distribution of free-standing silicon nanocrystals (Si-NCs) with multi-modal size distributions. The estimated size distributions are in excellent agreement with TEM and PL results, revealing the reliability of our model.

We demonstrate how to determine the size distribution of semiconductor nanocrystals in a quantitative manner using Raman spectroscopy employing an analytically defined multi-particle phonon confinement model. Results obtained are in excellent agreement with the other size analysis techniques like transmission electron microscopy and photoluminescence spectroscopy.

使用拉曼光谱与多颗粒的声子坐月子型号纳米大小分布的特征

Analysis of the size distribution of nanocrystals is a critical requirement for the processing and optimization of their size-dependent properties. The ...

Compact Lens-less Digital Holographic Microscope for MEMS Inspection and Characterization

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and automotive. However, effective inspection and characterization metrology systems are needed to ensure the functional reliability of MEMS. This study presents a system based on digital holography as a tool for MEMS metrology. Digital holography has gained increasing attention in the past 20 years. With the fast development and decreasing cost of sensor arrays, resolution of such systems has increased broadening potential applications. Thus, it has attracted attention from both research and industry sides as a potential reliable tool for industrial metrology. Indeed, by recording the interference pattern between an object beam (which contains sample height information) and a reference beam on a CCD camera, one can retrieve the quantitative phase information of an object. However, most of digital holographic systems are bulky and thus not easy to implement on industry production lines. The novelty of the system presented is that it is lens-less and thus very compact. In this study, it is shown that the Compact Digital Holographic Microscope (CDHM) can be used to evaluate several characteristics typically consider as criteria in MEMS inspections. The surface profiles of MEMS in both static and dynamic conditions are presented. Comparison with AFM is investigated to validate the accuracy of the CDHM.

We present a compact reflection digital holographic system (CDHM) for inspection and characterization of MEMS devices. A lens-less design using a diverging input wave providing natural geometrical magnification is demonstrated. Both static and dynamic studies are presented.

紧凑的镜头少数字全息显微镜的MEMS检测与表征

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

散装异质结太阳能电池的印刷和制作<em&gt;原位</em&gt;形态特征

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Experimental Methodology for Estimation of Local Heat Fluxes and Burning Rates in Steady Laminar Boundary Layer Diffusion Flames

Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex interactions occurring at the interface between gas-phase flames and condensed-phase fuels. The current research provides a technique to explore the dynamic relationship between a combustible condensed fuel surface and gas-phase flames in laminar boundary layers. Experiments have previously been conducted in both forced and free convective environments over both solid and liquid fuels. A unique methodology, based on the Reynolds Analogy, was used to estimate local mass burning rates and flame heat fluxes for these laminar boundary layer diffusion flames utilizing local temperature gradients at the fuel surface. Local mass burning rates and convective and radiative heat feedback from the flames were measured in both the pyrolysis and plume regions by using temperature gradients mapped near the wall by a two-axis traverse system. These experiments are time-consuming and can be challenging to design as the condensed fuel surface burns steadily for only a limited period of time following ignition. The temperature profiles near the fuel surface need to be mapped during steady burning of a condensed fuel surface at a very high spatial resolution in order to capture reasonable estimates of local temperature gradients. Careful corrections for radiative heat losses from the thermocouples are also essential for accurate measurements. For these reasons, the whole experimental setup needs to be automated with a computer-controlled traverse mechanism, eliminating most errors due to positioning of a micro-thermocouple. An outline of steps to reproducibly capture near-wall temperature gradients and use them to assess local burning rates and heat fluxes is provided.

We describe the use of micro-thermocouples to estimate local temperature gradients in steady laminar boundary layer diffusion flames. By extension of the Reynolds Analogy, local temperature gradients can be further used to estimate the local mass burning rates and heat fluxes in such flames with high accuracy.

在稳定层流边界层扩散火焰本地热通量和燃烧率的估计实验方法

Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex ...

A Guide to Concentration Alternating Frequency Response Analysis of Fuel Cells

An experimental setup capable of generating a periodic concentration input perturbation of oxygen was used to perform concentration-alternating frequency response analysis (cFRA) on proton-exchange membrane (PEM) fuel cells. During cFRA experiments, the modulated concentration feed was sent to the cathode of the cell at different frequencies. The electric response, which can be cell potential or current depending on the control applied on the cell, was registered in order to formulate a frequency response transfer function. Unlike traditional electrochemical impedance spectroscopy (EIS), the novel cFRA methodology makes it possible to separate the contribution of different mass transport phenomena from the kinetic charge transfer processes in the frequency response spectra of the cell. Moreover, cFRA is able to differentiate between varying humidification states of the cathode. In this protocol, the focus is on the detailed description of the procedure to perform cFRA experiments. The most critical steps of the measurements and future improvements to the technique are discussed.

We present a protocol for concentration alternating frequency response analysis of fuel cells, a promising new method of studying fuel cell dynamics.

燃料电池浓度交替频率响应分析指南

An experimental setup capable of generating a periodic concentration input perturbation of oxygen was used to perform concentration-alternating frequency ...

环境科学

Combustion Chemistry of Fuels: Quantitative Speciation Data Obtained from an Atmospheric High-temperature Flow Reactor with Coupled Molecular-beam Mass Spectrometer

This manuscript describes a high-temperature flow reactor experiment coupled to the powerful molecular beam mass spectrometry (MBMS) technique. This flexible tool offers a detailed observation of chemical gas-phase kinetics in reacting flows under well-controlled conditions. The vast range of operating conditions available in a laminar flow reactor enables access to extraordinary combustion applications that are typically not achievable by flame experiments. These include rich conditions at high temperatures relevant for gasification processes, the peroxy chemistry governing the low temperature oxidation regime or investigations of complex technical fuels. The presented setup allows measurements of quantitative speciation data for reaction model validation of combustion, gasification and pyrolysis processes, while enabling a systematic general understanding of the reaction chemistry. Validation of kinetic reaction models is generally performed by investigating combustion processes of pure compounds. The flow reactor has been enhanced to be suitable for technical fuels (e.g. multi-component mixtures like Jet A-1) to allow for phenomenological analysis of occurring combustion intermediates like soot precursors or pollutants. The controlled and comparable boundary conditions provided by the experimental design allow for predictions of pollutant formation tendencies. Cold reactants are fed premixed into the reactor that are highly diluted (in around 99 vol% in Ar) in order to suppress self-sustaining combustion reactions. The laminar flowing reactant mixture passes through a known temperature field, while the gas composition is determined at the reactors exhaust as a function of the oven temperature. The flow reactor is operated at atmospheric pressures with temperatures up to 1,800 K. The measurements themselves are performed by decreasing the temperature monotonically at a rate of -200 K/h. With the sensitive MBMS technique, detailed speciation data is acquired and quantified for almost all chemical species in the reactive process, including radical species.

An investigation of the oxidative combustion chemistry of novel biofuels, fuel components, or jet fuels by comparison of quantitative speciation data is presented. The data can be used for kinetic model validation and enables fuel assessment strategies.This manuscript describes the atmospheric high-temperature flow reactor and demonstrates its capabilities.

燃料燃烧化学: 用耦合分子束质谱仪从大气高温流反应器中获得的定量形态数据

This manuscript describes a high-temperature flow reactor experiment coupled to the powerful molecular beam mass spectrometry (MBMS) technique. This ...

化学

Improving the Combustion Performance of a Hybrid Rocket Engine using a Novel Fuel Grain with a Nested Helical Structure

A technique to improve the combustion performance of a hybrid rocket engine using a novel fuel grain structure is presented. This technique utilizes the different regression rates of acrylonitrile butadiene styrene and paraffin-based fuels, which increase the exchanges of both matter and energy by swirl flow and recirculation zones formed at the grooves between the adjacent vanes. The centrifugal casting technique is used to cast the paraffin-based fuel into an acrylonitrile butadiene styrene substrate made by three-dimensional printing. Using oxygen as the oxidizer, a series of tests were conducted to investigate the combustion performance of the novel fuel grain. In comparison to paraffin-based fuel grains, the fuel grain with a nested helical structure, which can be maintained throughout the combustion process, showed significant improvement in the regression rate and great potential in improvement of combustion efficiency.

A technique utilizing a solid fuel grain with a novel nested helical structure to improve the combustion performance of a hybrid rocket engine is presented.

使用具有嵌套的 Helical 结构的新颖燃料颗粒提高混合火箭发动机的燃烧性能

A technique to improve the combustion performance of a hybrid rocket engine using a novel fuel grain structure is presented. This technique utilizes the ...