本文主要研究内容
作者金凯强（2019）在《密闭管道内预混火焰传播动力学及抑制方法实验研究》一文中研究指出：随着经济发展和社会进步,化石能源日益枯竭,环境污染问题日益严重,全球对清洁可替代能源的需求与日俱增。可燃气体由于其清洁高效、来源广泛等优势而受到广泛的关注和青睐。然而,可燃气体通常具有易燃、易爆、易泄漏、点火能低等危险特性,一旦控制或使用不当,容易引发火灾爆炸等灾难事故。可燃气体在实际工业应用中主要通过管道进行输送。由于可燃气体控制难度较大,重大火灾和爆炸事故在全球范围内每年都有发生。因此,为了可燃气体的安全和工程应用需要,开展密闭管道内预混火焰传播动力学及抑制方法研究具有十分重要的战略意义。本文旨在研究密闭管道内预混火焰传播动力学特性,进而探索有效的预混火焰抑制方法。首先,通过预混火焰传播实验系统,对密闭管道内典型可燃气体-空气预混火焰传播动力学特性进行了对比研究。选用具有不同化学反应活性的四种可燃气体,包括甲烷、天然气、乙炔和氢气。采用高速纹影摄像系统捕捉火焰形状变化并确定火焰前锋速度,采用压力传感器记录压力随时间的变化过程。研究结果表明,可燃气体特性直接影响火焰行为。经典tulip火焰形成的当量比范围为:甲烷0.79≤Φ≤1.30,天然气0.72≤Φ≤.44,乙炔0.40≤Φ≤1.70,氢气0.60≤Φ≤5.56。变形tulip火焰形成的当量比范围为:乙炔Φ=1.00,氢气1.00≤Φ≤2.38,甲烷和天然气均没有形成变形tulip火焰。与纯甲烷相比,天然气中存在的少量乙烷和丙烷加速了火焰传播并增大了压力。同时,与天然气和甲烷相比,乙炔具有更快的火焰前锋速度和更高的压力。氢气由于具有最高的化学反应活性而产生了最快的火焰前锋速度和最大压力。当量比接近Φ=1.00时,Bychkov等人提出的火焰裙边运动理论预测结果与实验值吻合较好,该理论更适用于预测乙炔和氢气等高化学反应活性气体的火焰裙边运动特性。随后,分别选择甲烷和氢气作为低化学反应活性和高化学反应活性气体的代表,通过预混火焰抑制实验系统揭示了单层金属丝网和多层金属丝网对预混火焰传播特性的影响。研究结果表明,与无金属丝网的情况相比,金属丝网使得tulip火焰的形成时间提前,并且火焰前锋反转程度减弱。这主要归因于金属丝网能够提前火焰前锋与压力波的相互作用时间并削弱二者的相互作用强度。此外,金属丝网还增强了未燃区气体的气流扰动,并在火焰通过抑制段后产生更剧烈的燃烧。对于单层金属丝网,随着目数增加,火焰淬熄性能不会持续增强,因为其抗破坏性能在实际应用中也非常重要。由于未燃区气体流速的降低被可燃气体混合物燃烧速度的增大抵消,单层金属丝网对上游管道的火焰前锋速度没有明显抑制效果。多层金属丝网可以有效地衰减最大火焰前锋速度、最大压力和最大声音分贝值,并且抑制效果随着层数和目数的增加而增强。然后,系统地分析了多层金属丝网作用下火焰淬熄的影响因素,包括:可燃气体特性、温度和压力、可燃气体中的掺杂物、当量比、金属丝网体积、布置方式和点火位置等。研究发现,可燃气体特性、温度和压力、可燃气体中的掺杂物、当量比等通过影响层流燃烧速度进而影响火焰淬熄结果。明确了临界淬熄参数与金属丝网体积之间的关系。研究表明,随着金属丝网体积的增加,临界淬熄速度几乎呈线性增加。然而,最大临界淬熄压力保持在约0.115MPa的恒定值。与贫燃情况相比,金属丝网对富燃情况具有更好的抑制效果。此外,研究发现,通过改变金属丝网之间的间距可以改变其火焰淬熄性能。火焰是否发生淬熄其实只是火焰加速效应和壁面淬熄效应之间竞争的结果。点火位置显著影响火焰淬熄情况。对比了三个不同的点火位置,以确保火焰以三个不同的阶段传播到抑制段内。点火位置1时tulip火焰完全形成;点火位置2时火焰前锋曲率增大,tulip火焰尚未形成;点火位置3时为指尖形火焰。研究发现,点火位置越靠近金属丝网,火焰越容易发生淬熄。当火焰从管道封闭端开始时,tulip火焰本质上是由压力波和火焰前锋之间相互作用产生的涡旋导致的。然而,当火焰从管道中心开始时,具有较长尖端的tulip火焰主要是向上下游管道传播的火焰燃烧强度的巨大差异加剧已燃区气流逆向流动的结果。同时,研究表明,火焰从管道中心开始的情况下,向上游管道和下游管道传播的火焰前锋速度共同决定了管内压力动力学过程。最后,讨论了惰性气体和金属丝网对预混火焰传播的耦合抑制作用。研究发现,C02对氢-空气预混火焰的抑制效果比N2更好。富燃时,C02-5%对火焰前锋速度和压力几乎没有抑制作用,因为它对火焰表面积几乎没有影响。然而,在贫燃时,在CO2-5%的作用下,火焰前锋速度和压力都明显降低。随着浓度增加,抑制效果在25%之前持续增强,但随着浓度从25%增大到30%变得几乎恒定。C02浓度的增大能够抑制水力学不稳定性并减少火焰扰动。至于热扩散不稳定性,贫燃情况下CO2浓度的增大使得刘易斯数接近于1并减少火焰扰动。然而,富燃时热扩散不稳定性本身对水力学不稳定性具有一定抑制作用,CO2只是增强了这一效果并进一步减弱火焰扰动。CO2稀释和金属丝网对氢-空气预混火焰的耦合抑制作用比单独使用两种抑制剂中的任一种更有效。CO2稀释促进了金属丝网对贫燃氢-空气预混火焰的抑制作用,而金属丝网增强了CO2对富燃工况的抑制效果。此外,通过添加金属丝网,可以持续提高较高浓度CO2稀释对氢-空气预混火焰的抑制作用。
Abstract
sui zhao jing ji fa zhan he she hui jin bu ,hua dan neng yuan ri yi ku jie ,huan jing wu ran wen ti ri yi yan chong ,quan qiu dui qing jie ke ti dai neng yuan de xu qiu yu ri ju zeng 。ke ran qi ti you yu ji qing jie gao xiao 、lai yuan an fan deng you shi er shou dao an fan de guan zhu he qing lai 。ran er ,ke ran qi ti tong chang ju you yi ran 、yi bao 、yi xie lou 、dian huo neng di deng wei xian te xing ,yi dan kong zhi huo shi yong bu dang ,rong yi yin fa huo zai bao zha deng zai nan shi gu 。ke ran qi ti zai shi ji gong ye ying yong zhong zhu yao tong guo guan dao jin hang shu song 。you yu ke ran qi ti kong zhi nan du jiao da ,chong da huo zai he bao zha shi gu zai quan qiu fan wei nei mei nian dou you fa sheng 。yin ci ,wei le ke ran qi ti de an quan he gong cheng ying yong xu yao ,kai zhan mi bi guan dao nei yu hun huo yan chuan bo dong li xue ji yi zhi fang fa yan jiu ju you shi fen chong yao de zhan lve yi yi 。ben wen zhi zai yan jiu mi bi guan dao nei yu hun huo yan chuan bo dong li xue te xing ,jin er tan suo you xiao de yu hun huo yan yi zhi fang fa 。shou xian ,tong guo yu hun huo yan chuan bo shi yan ji tong ,dui mi bi guan dao nei dian xing ke ran qi ti -kong qi yu hun huo yan chuan bo dong li xue te xing jin hang le dui bi yan jiu 。shua yong ju you bu tong hua xue fan ying huo xing de si chong ke ran qi ti ,bao gua jia wan 、tian ran qi 、yi gui he qing qi 。cai yong gao su wen ying she xiang ji tong bu zhuo huo yan xing zhuang bian hua bing que ding huo yan qian feng su du ,cai yong ya li chuan gan qi ji lu ya li sui shi jian de bian hua guo cheng 。yan jiu jie guo biao ming ,ke ran qi ti te xing zhi jie ying xiang huo yan hang wei 。jing dian tuliphuo yan xing cheng de dang liang bi fan wei wei :jia wan 0.79≤Φ≤1.30,tian ran qi 0.72≤Φ≤.44,yi gui 0.40≤Φ≤1.70,qing qi 0.60≤Φ≤5.56。bian xing tuliphuo yan xing cheng de dang liang bi fan wei wei :yi gui Φ=1.00,qing qi 1.00≤Φ≤2.38,jia wan he tian ran qi jun mei you xing cheng bian xing tuliphuo yan 。yu chun jia wan xiang bi ,tian ran qi zhong cun zai de shao liang yi wan he bing wan jia su le huo yan chuan bo bing zeng da le ya li 。tong shi ,yu tian ran qi he jia wan xiang bi ,yi gui ju you geng kuai de huo yan qian feng su du he geng gao de ya li 。qing qi you yu ju you zui gao de hua xue fan ying huo xing er chan sheng le zui kuai de huo yan qian feng su du he zui da ya li 。dang liang bi jie jin Φ=1.00shi ,Bychkovdeng ren di chu de huo yan qun bian yun dong li lun yu ce jie guo yu shi yan zhi wen ge jiao hao ,gai li lun geng kuo yong yu yu ce yi gui he qing qi deng gao hua xue fan ying huo xing qi ti de huo yan qun bian yun dong te xing 。sui hou ,fen bie shua ze jia wan he qing qi zuo wei di hua xue fan ying huo xing he gao hua xue fan ying huo xing qi ti de dai biao ,tong guo yu hun huo yan yi zhi shi yan ji tong jie shi le chan ceng jin shu si wang he duo ceng jin shu si wang dui yu hun huo yan chuan bo te xing de ying xiang 。yan jiu jie guo biao ming ,yu mo jin shu si wang de qing kuang xiang bi ,jin shu si wang shi de tuliphuo yan de xing cheng shi jian di qian ,bing ju huo yan qian feng fan zhuai cheng du jian ruo 。zhe zhu yao gui yin yu jin shu si wang neng gou di qian huo yan qian feng yu ya li bo de xiang hu zuo yong shi jian bing xiao ruo er zhe de xiang hu zuo yong jiang du 。ci wai ,jin shu si wang hai zeng jiang le wei ran ou qi ti de qi liu rao dong ,bing zai huo yan tong guo yi zhi duan hou chan sheng geng ju lie de ran shao 。dui yu chan ceng jin shu si wang ,sui zhao mu shu zeng jia ,huo yan cui xi xing neng bu hui chi xu zeng jiang ,yin wei ji kang po huai xing neng zai shi ji ying yong zhong ye fei chang chong yao 。you yu wei ran ou qi ti liu su de jiang di bei ke ran qi ti hun ge wu ran shao su du de zeng da di xiao ,chan ceng jin shu si wang dui shang you guan dao de huo yan qian feng su du mei you ming xian yi zhi xiao guo 。duo ceng jin shu si wang ke yi you xiao de cui jian zui da huo yan qian feng su du 、zui da ya li he zui da sheng yin fen bei zhi ,bing ju yi zhi xiao guo sui zhao ceng shu he mu shu de zeng jia er zeng jiang 。ran hou ,ji tong de fen xi le duo ceng jin shu si wang zuo yong xia huo yan cui xi de ying xiang yin su ,bao gua :ke ran qi ti te xing 、wen du he ya li 、ke ran qi ti zhong de can za wu 、dang liang bi 、jin shu si wang ti ji 、bu zhi fang shi he dian huo wei zhi deng 。yan jiu fa xian ,ke ran qi ti te xing 、wen du he ya li 、ke ran qi ti zhong de can za wu 、dang liang bi deng tong guo ying xiang ceng liu ran shao su du jin er ying xiang huo yan cui xi jie guo 。ming que le lin jie cui xi can shu yu jin shu si wang ti ji zhi jian de guan ji 。yan jiu biao ming ,sui zhao jin shu si wang ti ji de zeng jia ,lin jie cui xi su du ji hu cheng xian xing zeng jia 。ran er ,zui da lin jie cui xi ya li bao chi zai yao 0.115MPade heng ding zhi 。yu pin ran qing kuang xiang bi ,jin shu si wang dui fu ran qing kuang ju you geng hao de yi zhi xiao guo 。ci wai ,yan jiu fa xian ,tong guo gai bian jin shu si wang zhi jian de jian ju ke yi gai bian ji huo yan cui xi xing neng 。huo yan shi fou fa sheng cui xi ji shi zhi shi huo yan jia su xiao ying he bi mian cui xi xiao ying zhi jian jing zheng de jie guo 。dian huo wei zhi xian zhe ying xiang huo yan cui xi qing kuang 。dui bi le san ge bu tong de dian huo wei zhi ,yi que bao huo yan yi san ge bu tong de jie duan chuan bo dao yi zhi duan nei 。dian huo wei zhi 1shi tuliphuo yan wan quan xing cheng ;dian huo wei zhi 2shi huo yan qian feng qu lv zeng da ,tuliphuo yan shang wei xing cheng ;dian huo wei zhi 3shi wei zhi jian xing huo yan 。yan jiu fa xian ,dian huo wei zhi yue kao jin jin shu si wang ,huo yan yue rong yi fa sheng cui xi 。dang huo yan cong guan dao feng bi duan kai shi shi ,tuliphuo yan ben zhi shang shi you ya li bo he huo yan qian feng zhi jian xiang hu zuo yong chan sheng de guo xuan dao zhi de 。ran er ,dang huo yan cong guan dao zhong xin kai shi shi ,ju you jiao chang jian duan de tuliphuo yan zhu yao shi xiang shang xia you guan dao chuan bo de huo yan ran shao jiang du de ju da cha yi jia ju yi ran ou qi liu ni xiang liu dong de jie guo 。tong shi ,yan jiu biao ming ,huo yan cong guan dao zhong xin kai shi de qing kuang xia ,xiang shang you guan dao he xia you guan dao chuan bo de huo yan qian feng su du gong tong jue ding le guan nei ya li dong li xue guo cheng 。zui hou ,tao lun le duo xing qi ti he jin shu si wang dui yu hun huo yan chuan bo de ou ge yi zhi zuo yong 。yan jiu fa xian ,C02dui qing -kong qi yu hun huo yan de yi zhi xiao guo bi N2geng hao 。fu ran shi ,C02-5%dui huo yan qian feng su du he ya li ji hu mei you yi zhi zuo yong ,yin wei ta dui huo yan biao mian ji ji hu mei you ying xiang 。ran er ,zai pin ran shi ,zai CO2-5%de zuo yong xia ,huo yan qian feng su du he ya li dou ming xian jiang di 。sui zhao nong du zeng jia ,yi zhi xiao guo zai 25%zhi qian chi xu zeng jiang ,dan sui zhao nong du cong 25%zeng da dao 30%bian de ji hu heng ding 。C02nong du de zeng da neng gou yi zhi shui li xue bu wen ding xing bing jian shao huo yan rao dong 。zhi yu re kuo san bu wen ding xing ,pin ran qing kuang xia CO2nong du de zeng da shi de liu yi si shu jie jin yu 1bing jian shao huo yan rao dong 。ran er ,fu ran shi re kuo san bu wen ding xing ben shen dui shui li xue bu wen ding xing ju you yi ding yi zhi zuo yong ,CO2zhi shi zeng jiang le zhe yi xiao guo bing jin yi bu jian ruo huo yan rao dong 。CO2xi shi he jin shu si wang dui qing -kong qi yu hun huo yan de ou ge yi zhi zuo yong bi chan du shi yong liang chong yi zhi ji zhong de ren yi chong geng you xiao 。CO2xi shi cu jin le jin shu si wang dui pin ran qing -kong qi yu hun huo yan de yi zhi zuo yong ,er jin shu si wang zeng jiang le CO2dui fu ran gong kuang de yi zhi xiao guo 。ci wai ,tong guo tian jia jin shu si wang ,ke yi chi xu di gao jiao gao nong du CO2xi shi dui qing -kong qi yu hun huo yan de yi zhi zuo yong 。
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论文详细介绍
论文作者分别是来自中国科学技术大学的金凯强，发表于刊物中国科学技术大学2019-07-12论文，是一篇关于预混火焰论文,纹影论文,火焰前锋动力学论文,压力动力学论文,抑制论文,金属丝网论文,惰性气体论文,耦合作用论文,中国科学技术大学2019-07-12论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自中国科学技术大学2019-07-12论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：预混火焰论文; 纹影论文; 火焰前锋动力学论文; 压力动力学论文; 抑制论文; 金属丝网论文; 惰性气体论文; 耦合作用论文; 中国科学技术大学2019-07-12论文;