Flow field visualization for ethylene/air auto-ignition at different pressures and temperatures in a rectangular shock tube
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摘要: 为认识不同压力（p5）和温度（T5）的乙烯/空气自点火和火焰传播特征，在矩形激波管中，采用火焰自发光信号触发高速ICCD相机拍摄了反射激波后流场，得到了不同工况下乙烯/空气自点火流场序列图像。结果表明：对p5=106kPa，当T5=1210K，点火首先发生在激波管反射端面附近，向上游（右侧）传播并形成近似平面火焰。火焰面随时间推进趋于垂直激波管轴线，火焰在传播过程中厚度近似保持不变，且内部存在漩涡结构。当降低T5，自点火位置逐渐远离反射端面，初始火焰厚度增大且光强变弱，由单个平面火焰演变为多个离散的不规则火焰。当T5=1077K，初始火焰首先出现在观察窗右侧（远离反射端面）并向上下游传播。当增大p5，火焰光强增大且漩涡尺寸减小，不同p5对应的火焰产生和传播规律类似。当p5=265和419kPa，火焰内部产生局部爆炸现象，多个局部爆炸区在传播过程中不断融合，最终形成向上游传播的近似平面火焰。Abstract: Flow field visualization for the auto-ignition of the ethylene/air mixture is key important in understanding properties and characteristics of the flame generation and propagation. High-speed photography was used in experiments and ICCD camera was triggered by the flame signal located at the test section. The series of images for the auto-ignition flow field were obtained at different temperatures (T5) and pressures (p5) in a rectangular shock tube. In the case of p5 being 106kPa, auto-ignition occurs and the initial flame is close to the tube end of shock reflection when T5 is 1210K. Then, the flame propagates upstream (right side) and evolves as a planar one. The vortex-lets are obviously embedded in the flame surface. The flame front gradually evolves to be vertical to the tube axis as it propagates upstream. In contrast to decreasing T5, the initial flame becomes thicker and moves away from the tube end of shock reflection. More-over, the flame emission becomes weaker corresponding to the lower reaction rate. Also, the flame decays from a planar front into several irregular zones. When T5 is 1077K, the auto-ignition occurs far away from the tube end of shock reflection, and then propagates upstream and downstream. With increasing p5, the flames emit strongly and the vortex-lets almost disappear on flame surfaces. When p5 are 265 and 419kPa, respectively, the local explosions take place frequently. These local explosions merge into an approximately planar front and propagate upstream with time going by.
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Key words:
- shock tube /
- ethylene /
- auto-ignition /
- flow filed imaging /
- flame
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表 1 相同工况参数列表(case 1和2)
Table 1. Parameters for the same cases (case 1 and 2)
Case φ Mas p5/kPa T5/K τig/μs 1 1.0 2.984 106 1210 51 2 1.0 3.016 108 1229 47 
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表 2 火焰平均传播速度(case 1和2)
Table 2. Mean velocities of flame propagation (case 1 and 2)
Case uab
/(m·s-1)ubc
/(m·s-1)ucd
/(m·s-1)Δuab
/(m·s-1)Δubc
/(m·s-1)Δucd
/(m·s-1)1 845 680 801 1616 1451 1572 2 833 1328 1134 1614 2109 1915
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表 3 不同温度工况参数列表(case 3~6)
Table 3. Parameters for cases at different temperatures (case 3~6)
Case φ Mas p5/kPa T5/K τig/μs 3 1.0 3.127 109 1294 12 4 1.0 2.857 101 1138 223 5 1.0 2.806 106 1109 418 6 1.0 2.748 98 1077 728
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表 4 不同压力工况参数列表(case 7~14)
Table 4. Parameters for cases at different pressures (case 7~14)
Case φ Mas p5/kPa T5/K τig/μs 7 1.0 3.073 267 1252 19 8 1.0 3.293 433 1384 0 9 1.0 2.871 271 1136 122 10 1.0 2.926 423 1167 163 11 1.0 2.826 254 1111 539 12 1.0 2.818 375 1107 399 13 1.0 2.767 265 1079 945 14 1.0 2.724 444 1055 723
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[1] Hanson R K, Davidson D F. Recent advances in laser absorption and shock tube methods for studies of combustion chemistry[J]. Progress in Energy & Combustion Science, 2014, 44(5):103-114. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=32a48adc67662fe720c9b40098405349 [2] Ren W, Davidson D F, Hanson R K. IR laser absorption diagnostic for C2H4 in shock tube kinetics studies[J]. International Journal of Chemical Kinetics, 2012, 44(6):423-432. doi: 10.1002/kin.v44.6 [3] Barari G, Pryor O, Koroglu B, et al. High temperature shock tube experiments and kinetic modeling study of diisopropyl ketone ignition and pyrolysis[J]. Combustion & Flame, 2017, 177:207-218. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=44a2d934b262dc7667b3fd5aa0b0fe26 [4] Ning H B, Wu J J, Ma L H, et al. Combined ab initio, kinetic modeling, and shock tube study of the thermal decomposition of ethyl formate[J]. The Journal of Physical Chemistry A, 2017, 121(35):6568-6579. doi: 10.1021/acs.jpca.7b05382 [5] 李兰, 陈其盛, 赵文涛.基于成像的RP-3煤油在激波管内自点火过程研究[J].推进技术, 2015, 36(10):1504-1508. http://d.old.wanfangdata.com.cn/Periodical/tjjs201510008Li L, Chen Q S, Zhao W T. A study of RP-3 autoignition in shock tube based on imaging[J]. Journal of Propulsion Techno-logy, 2015, 36(10):1504-1508. http://d.old.wanfangdata.com.cn/Periodical/tjjs201510008 [6] 廖钦.煤油及其裂解产物自点火现象的初步实验研究[D].合肥: 中国科学技术大学, 2009. http://cdmd.cnki.com.cn/Article/CDMD-10358-2009110958.htmLiao Q. Experimental studies on autoignition phnomena of kerosene and cracked kerosene in a shock tube[D]. Hefei: University of Science and Technology of China, 2009. http://cdmd.cnki.com.cn/Article/CDMD-10358-2009110958.htm [7] 王高峰.基于激波管实验平台的甲烷燃烧化学动力学机理研究[D].合肥: 中国科学技术大学, 2008. http://cdmd.cnki.com.cn/Article/CDMD-10358-2009024956.htmWang G F. A shock tube study of methane combustion chemical kinetics mechanism[D]. Hefei: University of Science and Technology of China, 2008. http://cdmd.cnki.com.cn/Article/CDMD-10358-2009024956.htm [8] Herzler J, Jerig L, Roth P. Shock-tube study of the ignition of propane at intermediate temperatures and high pressures[J]. Combustion Science & Technology, 2004, 176(10):1627-1637. http://cn.bing.com/academic/profile?id=bec22ebed9618b4f4e3a2dae9a8b0e70&encoded=0&v=paper_preview&mkt=zh-cn [9] 胡弘浩.乙烯点火特性及其污染效应的激波管研究[D].重庆: 重庆大学, 2012. http://cdmd.cnki.com.cn/Article/CDMD-10611-1012049448.htmHu H H. A shock tube study of ignition delay characteristics of ethylene and comtamination effect[D]. Chongqing: Chongqing University, 2012. http://cdmd.cnki.com.cn/Article/CDMD-10611-1012049448.htm [10] Baker J A, Skinner G B. Shock-tube studies on the ignition of ethylene-oxygen-argon mixtures[J]. Combustion & Flame, 1972, 19(3):347-350. http://cn.bing.com/academic/profile?id=d47422c247a6bfc2c9a72aece709c7cb&encoded=0&v=paper_preview&mkt=zh-cn [11] Suzuki M, Moriwaki T, Okazaki S, et al. Oxidation of ethylene in shock tube[J]. Astronautica Acta, 1973, 18(5):359-365. http://cn.bing.com/academic/profile?id=8ee245eea4938d57a7aa5d612a979c44&encoded=0&v=paper_preview&mkt=zh-cn [12] Brown C J, Thomas G O. Experimental studies of shock-induced ignition and transition to detonation in ethylene and propane mixtures[J]. Combustion & Flame, 1999, 117(4):861-870. http://cn.bing.com/academic/profile?id=45b8d493fc3ef59ad3bd48381bc9e406&encoded=0&v=paper_preview&mkt=zh-cn [13] Cadman P, Bambrey R J, Box S K, et al. Ethylene combustion studied over a wide temperature range in high-temperature shock waves[J]. Combustion Science & Technology, 2002, 174(11-2):111-127. http://cn.bing.com/academic/profile?id=0024ddd0f00d3b071b32ebe639cf0bae&encoded=0&v=paper_preview&mkt=zh-cn [14] Saxena S, Kahandawala M S P, Sidhu S S. A shock tube study of ignition delay in the combustion of ethylene[J]. Combustion & Flame, 2011, 158(6):1019-1031. http://cn.bing.com/academic/profile?id=e1b428a0420bc7aa851798c81f57e8fc&encoded=0&v=paper_preview&mkt=zh-cn [15] 梁金虎.煤油点火延时特性及其污染效应的激波管研究[D].重庆: 重庆大学, 2011. http://cdmd.cnki.com.cn/Article/CDMD-10611-1012008763.htmLiang J H. Ignition delay characteristics study of kerosene and contaminated kerosene in shock tube[D]. Chongqing: Chongqing University, 2011. http://cdmd.cnki.com.cn/Article/CDMD-10611-1012008763.htm [16] Deng F Q, Pan Y S, Sun W C, et al. Comparative study of the effects of nitrous oxide and oxygen on ethylene ignition[J]. Energy & Fuels, 2017, 31(12):14116-14128. http://cn.bing.com/academic/profile?id=ad573a7c017db8d45d134c5159eb9dc9&encoded=0&v=paper_preview&mkt=zh-cn [17] Pfahl U, Fieweger K and Adomeit G. Self-ignition of diesel-relevant hydrocarbon-air mixtures under engine conditions[J]. Symposium (International) on Combustion, 1996, 26(1):781-789. doi: 10.1016/S0082-0784(96)80287-6 -
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