本文選題：煤塵-甲烷預混燃燒 + 火焰?zhèn)鞑ソY構�。� 參考：《武漢理工大學》2015年碩士論文

【摘要】：課題通過搭建煤塵-甲烷預混物燃燒火焰特性實驗平臺,結合高速攝像機、數據采集儀和溫度傳感器等,測量得到不同條件下煤塵-甲烷預混燃燒火焰?zhèn)鞑バ螒B(tài)圖、傳播速度、溫度等火焰?zhèn)鞑ヌ卣鲄?并分析煤塵-甲烷預混燃燒火焰的傳播特性以及煤塵粒徑和甲烷濃度對混合物燃燒火焰?zhèn)鞑ヌ匦缘挠绊憽５贸鲆韵陆Y論:(1)煤塵-甲烷預混燃燒火焰?zhèn)鞑バ螒B(tài)以及燃燒強度與甲烷濃度以及煤塵粒徑密切相關。甲烷濃度為3.7%時,火焰前鋒呈離散不規(guī)則狀態(tài),而當甲烷濃度增大為4.5%、6.7%時,火焰前鋒呈較規(guī)則的平面或拋物面;當煤塵粒徑較小時,燃燒火焰前沿較為規(guī)則連續(xù),且發(fā)出較為強烈的白光,表明燃燒較為劇烈,而隨著煤塵粒徑的增大,燃燒火焰前沿趨向于離散不規(guī)則狀態(tài),發(fā)出紅黃色光,表明燃燒強度降低。(2)在預混燃燒火焰?zhèn)鞑ミ^程中,甲烷燃燒火焰放熱和粒徑大小影響熱電偶溫度上升時間,但主要是甲烷濃度決定熱電偶溫度上升時間;煤塵粒子燃燒決定火焰溫度最大值。在煤塵粒徑較大(54-74μm)時,不同甲烷濃度的溫度上升時間差別很大;煤塵粒徑減小時,甲烷濃度為3.7%和4.5%的溫度上升時間差別不大,但甲烷濃度為6.7%的溫度上升時間差別較大;6.7%的甲烷濃度的火焰溫度在預混物點燃很短的時間內及開始上升。隨煤塵粒徑增大,由于煤塵粒子的反應速率和釋放的能量都降低,火焰溫度整體隨煤塵粒徑增大而減小,但中間略有波動。(3)火焰?zhèn)鞑ニ俣仁怯杉淄楹兔悍酃餐瑳Q定的,其中甲烷對火焰?zhèn)鞑ニ俣扔绊戇h遠大于煤粉,而煤粉的火焰?zhèn)鞑ニ俣入S粒徑的增大而減小,因此,當煤粉粒徑小于30-38.5μm時,甲烷濃度對預混火焰的傳播起主導作用,6.7%甲烷濃度的預混火焰?zhèn)鞑ニ俣冗h遠大于3.7%和4.5%甲烷濃度;當煤粉粒徑大于30-38.5μm時,煤粉粒徑開始影響預混火焰的傳播特性,導致火焰?zhèn)鞑ニ俣冉档�。同時,課題分別采用單步化學反應模型(the single kinetic rate model)和擴散-動力控制燃燒模型(the kinetics/diffusion-limited rate model)重現煤塵-甲烷混合物的預混燃燒過程。通過分析燃燒管道中煤塵-甲烷混合物的預混燃燒的火焰圖像以及火焰溫度,并結合數值模擬方法,得出以下結論:(4)由煤塵-甲烷預混燃燒的數值模擬結果表明,預混火焰的前鋒位置以甲烷燃燒為主,而對于煤塵粒子,小部分熱量在火焰前鋒內釋放,但在火焰前鋒過后,煤塵粒子依然持續(xù)燃燒較長的時間,并釋放出它的大部分熱量。(5)根據煤塵-甲烷預混燃燒火焰鋒面處的溫度和化學反應速率數值模擬云圖可得到預熱區(qū)厚度。在不同實驗條件下煤塵-甲烷預混燃燒火焰的預熱區(qū)厚度在2~16mm范圍之間,且隨煤塵粒徑的增大,火焰?zhèn)鞑ニ俣冉档?熱量傳播時間增加,在相同的熱傳導速率條件下預熱區(qū)厚度增加。隨甲烷濃度增大,甲烷燃燒反應速率增高、釋放熱量增多,傳遞給預熱區(qū)的熱量增多,使得預熱區(qū)厚度增大。
[Abstract]:The characteristics of the flame combustion experimental platform blends to build coal - methane pre, combined with high speed camera, data acquisition instrument and temperature sensors, the measured under different conditions of coal - methane premixed combustion flame shape map, propagation speed, the flame propagation characteristic parameters of temperature, and the analysis of coal - methane premixed combustion flame and the characteristics of coal dust particle size and concentration of methane on flame propagation characteristics of combustion of the mixture effect. Draw the following conclusions: (1) the burning flame shape and combustion intensity and concentration of methane and coal dust particle size is closely related to pre mixed coal methane. Methane concentration is 3.7%, the flame front is discrete and irregular, and when the concentration of methane increase of 4.5%, 6.7%, the flame front had a regular plane or paraboloid; when the dust particle size is small, the flame front is regular and continuous, the strong white hair The light indicates that the combustion is more severe, and with the increasing of the size of coal dust particle, the flame front tends to discrete and irregular state, a red and yellow light, indicating that the combustion intensity decreased. (2) in the premixed combustion flame propagation, flame heat and particle size effect of thermocouple temperature rise time of methane combustion, but mainly the methane concentration determines the thermocouple temperature rise time; coal dust combustion to determine the maximum flame temperature in coal dust. The larger particle size (54-74 m), different methane concentration temperature rise time difference; dust particle size decreases, methane concentration is 3.7% and 4.5% of the temperature rise time had little difference, but the methane concentration is 6.7% the temperature rise time difference; 6.7% of the methane concentration in the premixed flame temperature are ignited in a very short period of time and began to rise. With increasing diameter of coal dust particle, the reaction rate and the release of dust particles Energy is reduced, the temperature of the flame with the dust particle size decreases, but slight fluctuations. (3) the flame propagation velocity is determined by methane and coal, the effects of methane on flame propagation speed is far greater than that of pulverized coal, and the flame propagation velocity of pulverized coal with the particle size decreasing, therefore, when the coal the particle size is less than 30-38.5 m, the pre mixed flame propagation of methane concentration plays a dominant role, 6.7% concentration of methane premixed flame propagation speed is far greater than the 3.7% and 4.5% methane concentration; when the particle diameter is larger than 30-38.5 m, the propagation characteristics of pulverized coal particle size began to influence the premixed flame, the flame propagation speed reduced. At the same time, paper by a one-step chemical reaction model (the single kinetic rate model) and diffusion kinetic control combustion model (the kinetics/diffusion-limited rate model) to reproduce the coal - methane mixture premixed combustion Burning process. Through the analysis of the combustion pipe in coal - methane mixture premixed combustion flame image and flame temperature, and combining with numerical simulation, draw the following conclusions: (4) numerical simulation by coal - methane premixed combustion. The results show that the forward position of premixed flame in combustion of methane, and for coal dust particles small part of the heat release, the flame front, but after the dust particles in the flame front, still continue to burn for a longer time, and most of the heat release of it. (5) according to the flame temperature and chemical reaction rate can be obtained by numerical simulation of cloud thickness preheating zone combustion of blended coal methane in coal - pre. Under different experimental conditions of methane premixed combustion flame preheating zone thickness in the range of 2~16mm, and with the increase of the diameter of coal dust particle, the flame propagation speed is reduced, the heat transmission time increases, in the same heat conduction velocity The thickness of preheating area increased with the increase of methane concentration, and the rate of methane combustion increased, the amount of heat released increased, the heat transferred to the preheating area increased, and the thickness of preheating area increased.

【學位授予單位】：武漢理工大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TD714.5;O643.21

【參考文獻】

相關期刊論文 前10條

1 王育德;曲志明;;煤塵濃度和粒度對煤塵燃燒爆炸特性影響的實驗研究[J];中國礦業(yè);2013年08期

2 曲志明;王育德;;甲烷煤塵燃燒爆炸試驗研究[J];中國安全科學學報;2012年11期

3 牛芳;劉慶明;白春華;何學秋;宮廣東;;甲烷-煤塵爆炸物火焰?zhèn)鞑ヌ匦訹J];高壓物理學報;2012年04期

4 丁以斌;孫金華;何學超;尹藝;徐耀;黃新杰;;鋯粉塵云的火焰?zhèn)鞑ヌ匦訹J];燃燒科學與技術;2010年04期

5 吳紅波;陸守香;張立;;瓦斯火焰誘導沉積煤塵燃燒爆炸機理的實驗研究[J];火工品;2009年01期

6 陳東梁;孫金華;劉義;王青松;;甲烷/煤塵復合體系燃燒反應特性研究[J];工程熱物理學報;2008年07期

7 本刊編輯部;;從重從嚴打擊責任事故犯罪[J];勞動保護;2007年06期

8 陳東梁;孫金華;劉義;陳思凝;王青松;;甲烷、煤塵復合體系燃燒特性及火焰結構的實驗研究[J];自然科學進展;2007年04期

9 孫金華,盧平,劉義;空氣中懸浮金屬微粒子的燃燒特性[J];南京理工大學學報(自然科學版);2005年05期

10 孫金華;PMMA微粒子云中傳播火焰的基本結構[J];熱科學與技術;2004年01期

相關博士學位論文 前3條

1 董呈杰;甲烷—沉積煤塵爆炸實驗與大渦模擬[D];大連理工大學;2012年

2 丁以斌;鋯粉云火焰?zhèn)鞑ヌ匦缘膶嶒炑芯縖D];中國科學技術大學;2010年

3 陳東梁;甲烷/煤塵復合火焰?zhèn)鞑ヌ匦约皺C理的研究[D];中國科學技術大學;2007年

相關碩士學位論文 前1條

1 陳玲;鋁粉爆炸特性的實驗研究和數值模擬[D];大連理工大學;2011年

，

本文編號：1745785