高壓氮?dú)鉀_擊致裂煤巖體裂隙發(fā)育規(guī)律研究
本文選題：高壓氮?dú)?/strong> + 氣射流 ； 參考：《中國礦業(yè)大學(xué)》2017年碩士論文
【摘要】：氮?dú)庾鳛槎栊詺怏w,在煤中不容易被吸附存儲;當(dāng)高壓氮?dú)庠诿簩又邪l(fā)生沖擊致裂后,不會留存大量的膨脹能,不具有突出危險(xiǎn)性。隨著我國開采深度的增加,礦井的瓦斯含量隨之上升而滲透率同時(shí)下降,通過在煤層中實(shí)施高壓氮?dú)庵铝芽梢蕴岣咄咚钩椴陕�、降低瓦斯含量。因�?高壓氮?dú)鉀_擊致裂的研究對于礦井的安全生產(chǎn)具有重要意義。本文以對高壓氮?dú)鈿馍淞鳑_擊過程以及高壓氮?dú)獾臏?zhǔn)靜態(tài)膨脹作用的研究為基礎(chǔ),分析了致裂過程中能量的變化,并以之作為理論指導(dǎo)開展高壓氮?dú)鉀_擊致裂實(shí)驗(yàn)與數(shù)值模擬研究,獲得了不同工況下高壓氮?dú)鉀_擊致裂的相關(guān)規(guī)律。實(shí)驗(yàn)系統(tǒng)以高壓氮?dú)鉀_擊致裂裝置為核心,主要由高壓氮?dú)鉀_擊致裂系統(tǒng)和實(shí)時(shí)監(jiān)控系統(tǒng)兩部分組成實(shí)驗(yàn)系統(tǒng)。其中高壓氮?dú)庵铝严到y(tǒng)包括高壓氮?dú)鈮毫υ�、高壓氮�(dú)鉀_擊致裂實(shí)驗(yàn)裝置、氣動高壓切斷球閥、試塊以及連接裝置等部分。實(shí)驗(yàn)中采用毫秒級壓力傳送器以及聲發(fā)射監(jiān)測系統(tǒng),對致裂過程中壓力的升降和試塊內(nèi)部的能量等物理量的變化進(jìn)行監(jiān)測。通過強(qiáng)度測定等實(shí)驗(yàn)確定了不同強(qiáng)度相似材料的配比并確定28天的養(yǎng)護(hù)周期;同時(shí)通過應(yīng)力加載的方式來模擬煤層在實(shí)際情況中應(yīng)力場的情況。實(shí)驗(yàn)中采用1L的容器作為氣體的初始體積,分別先對三種強(qiáng)度的試塊進(jìn)行初始壓力為5MPa、7.5MPa以及10MPa三種工況條件下的沖擊致裂實(shí)驗(yàn);再改變?nèi)N強(qiáng)度試塊的應(yīng)力環(huán)境進(jìn)行初始壓力為5MPa的實(shí)驗(yàn)。從結(jié)果分析得出隨著氣體初始壓力的升高,裂紋從最初只有一條縱向裂紋到隨后以釋放孔為中心呈星狀發(fā)散的裂紋,從垂直于最小主應(yīng)力方向到均勻分布。同時(shí)裂紋的分布于試塊周邊的應(yīng)力差也有一定關(guān)系,應(yīng)力差小則裂紋均勻分布,應(yīng)力差大則垂直于最小主應(yīng)力方向。再此基礎(chǔ)上對于最小致裂壓力進(jìn)行了初步研究,結(jié)果圈定在2MPa-3MPa之間。根據(jù)對壓力監(jiān)測結(jié)果的分析,整個(gè)高壓氮?dú)庵铝堰^程根據(jù)壓力上升的快慢可以分為氣體射流沖擊階段、起裂致裂階段和動態(tài)止裂階段。從聲發(fā)射監(jiān)測結(jié)果中得出,隨著氣體壓力的上升,試塊致裂時(shí)內(nèi)部絕對能量也呈現(xiàn)上升趨勢,尤其是在7.5MPa升至10MPa時(shí)能量上升明顯。以理論研究為基礎(chǔ)結(jié)合現(xiàn)場實(shí)際,通過ANSYS/LS-DYNA模擬軟件建立模型進(jìn)行精算并通過LS_PREPOST后處理,對5MPa、7.5MPa和10MPa三種工況下的高壓氮?dú)鉀_擊致裂進(jìn)行模擬。從模擬的運(yùn)行過程中可以看出,裂隙的發(fā)育情況隨著氣體初始壓力的升高而得到明顯的提升,同時(shí)裂隙呈現(xiàn)出先沿軸向再沿徑向擴(kuò)展的變化規(guī)律,這一規(guī)律在應(yīng)力云圖中也得到了驗(yàn)證。通過對應(yīng)力波傳遞結(jié)果的分析得出,致裂過程中的應(yīng)力波呈現(xiàn)震動上升,當(dāng)應(yīng)力值大于煤層失效應(yīng)力時(shí),致裂發(fā)生;小于時(shí)則保持高應(yīng)力狀態(tài)直至發(fā)生致裂。
[Abstract]:Nitrogen, as an inert gas, is not easily adsorbed and stored in coal. With the increase of mining depth in China, the gas content in coal mine increases and the permeability decreases simultaneously. The gas extraction rate can be increased and the gas content can be reduced by the application of high pressure nitrogen in coal seam. Therefore, the research of high pressure nitrogen impact cracking is of great significance to mine safety production. Based on the study of the impinging process of high pressure nitrogen jet and the quasi-static expansion of high pressure nitrogen, the energy changes during the process of cracking are analyzed. The experiment and numerical simulation of high pressure nitrogen impact cracking were carried out under the guidance of the theory, and the related laws of high pressure nitrogen impact cracking under different working conditions were obtained. The experimental system is composed of two parts: high pressure nitrogen impact cracking system and real time monitoring system. The high pressure nitrogen fracturing system includes high pressure nitrogen pressure source, high pressure nitrogen impact cracking experimental device, pneumatic high pressure cut off ball valve, test block and connecting device and so on. In the experiment, millisecond pressure transmitter and acoustic emission monitoring system are used to monitor the change of physical quantities such as pressure rise and fall and energy inside the specimen during the process of cracking. The proportioning of similar materials with different strength and the curing period of 28 days were determined by strength measurement, and the stress field of coal seam was simulated by the way of stress loading. In the experiment, 1L vessel was used as the initial volume of gas, and the initial pressure of three kinds of strength samples was tested under the initial pressure of 5 MPA and 7.5 MPA, respectively, and the impact cracking test was carried out under three conditions of 10MPa. Then the stress environment of the three strength specimens was changed and the initial pressure was 5MPa. The results show that with the increase of the initial gas pressure, the crack changes from one longitudinal crack to a star-shaped crack centered on the release hole, from the direction perpendicular to the minimum principal stress to the uniform distribution. At the same time, the distribution of the crack is also related to the stress difference around the specimen. The crack distributes evenly when the stress difference is small, and the stress difference is perpendicular to the direction of the minimum principal stress. On this basis, a preliminary study of the minimum cracking pressure is carried out, and the results are delineated between 2MPa-3MPa. According to the analysis of pressure monitoring results, the whole process of high pressure nitrogen cracking can be divided into three stages: gas jet impingement stage, crack initiation stage and dynamic crack arrest stage according to the speed of pressure rise. From the results of acoustic emission monitoring, it can be concluded that with the increase of gas pressure, the internal absolute energy of the specimen also shows an upward trend, especially when 7.5MPa rises to 10MPa. On the basis of theoretical research and field practice, the model was established by ANSYS/LS-DYNA simulation software and LS_PREPOST post-treatment was used to simulate the impact cracking of high pressure nitrogen under three conditions: 5MPA 7.5MPa and 10MPa. It can be seen from the operation of the simulation that the development of fractures increases obviously with the increase of the initial gas pressure, and the fracture shows a variation law of first axial direction and then radial expansion. This rule is also verified in the stress cloud diagram. Through the analysis of the results of stress wave transmission, it is concluded that the stress wave in the process of crack appears vibration rising, when the stress value is greater than the failure stress of coal seam, the crack occurs, and when the stress value is larger than the failure stress of coal seam, the stress wave will remain in a high stress state until the crack occurs.
【學(xué)位授予單位】：中國礦業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TD712.6
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 謝子令;李顯;;養(yǎng)護(hù)溫度及時(shí)間對粉煤灰基地質(zhì)聚合物混凝土強(qiáng)度發(fā)展的影響[J];混凝土;2014年06期
2 趙立朋;;煤層液態(tài)CO_2深孔爆破增透技術(shù)[J];煤礦安全;2013年12期
3 袁亮;薛俊華;張農(nóng);盧平;;煤層氣抽采和煤與瓦斯共采關(guān)鍵技術(shù)現(xiàn)狀與展望[J];煤炭科學(xué)技術(shù);2013年09期
4 張連軍;林柏泉;高亞明;;高壓水力割縫技術(shù)在快速掘進(jìn)中的應(yīng)用[J];能源技術(shù)與管理;2013年04期
5 覃道雄;朱紅青;張民波;申健;楊成軼;;煤層水力壓裂增透技術(shù)研究與應(yīng)用[J];煤炭科學(xué)技術(shù);2013年05期
6 袁亮;薛俊華;;低透氣性煤層群無煤柱煤與瓦斯共采關(guān)鍵技術(shù)[J];煤炭科學(xué)技術(shù);2013年01期
7 涂敏;袁亮;繆協(xié)興;劉澤功;徐乃忠;付寶杰;;保護(hù)層卸壓開采煤層變形與增透效應(yīng)研究[J];煤炭科學(xué)技術(shù);2013年01期
8 楊宏偉;;低透氣性煤層井下分段點(diǎn)式水力壓裂增透[J];北京科技大學(xué)學(xué)報(bào);2012年11期
9 張建國;林柏泉;翟成;;穿層鉆孔高壓旋轉(zhuǎn)水射流割縫增透防突技術(shù)研究與應(yīng)用[J];采礦與安全工程學(xué)報(bào);2012年03期
10 翟成;李賢忠;李全貴;;煤層脈動水力壓裂卸壓增透技術(shù)研究與應(yīng)用[J];煤炭學(xué)報(bào);2011年12期
相關(guān)博士學(xué)位論文 前7條
1 田坤云;高壓水載荷下煤體變形特性及瓦斯?jié)B流規(guī)律研究[D];中國礦業(yè)大學(xué)（北京）;2014年
2 付江偉;井下水力壓裂煤層應(yīng)力場與瓦斯流場模擬研究[D];中國礦業(yè)大學(xué);2013年
3 楊宏民;井下注氣驅(qū)替煤層甲烷機(jī)理及規(guī)律研究[D];河南理工大學(xué);2010年
4 王志亮;煤層深孔預(yù)裂爆破裂隙擴(kuò)展機(jī)理與應(yīng)用研究[D];中國礦業(yè)大學(xué)（北京）;2010年
5 李清;爆炸致裂的巖石動態(tài)力學(xué)行為與斷裂控制試驗(yàn)研究[D];中國礦業(yè)大學(xué)（北京）;2009年
6 黃炳香;煤巖體水力致裂弱化的理論與應(yīng)用研究[D];中國礦業(yè)大學(xué);2009年
7 王亮;巨厚火成巖下遠(yuǎn)程卸壓煤巖體裂隙演化與滲流特征及在瓦斯抽采中的應(yīng)用[D];中國礦業(yè)大學(xué);2009年
相關(guān)碩士學(xué)位論文 前9條
1 常琳;地下車庫射流風(fēng)機(jī)排煙研究[D];北京工業(yè)大學(xué);2015年
2 孫建中;基于不同爆破致裂方式的液態(tài)二氧化碳相變增透應(yīng)用研究[D];中國礦業(yè)大學(xué);2015年
3 謝姣;基于Ansys/ls-dyna數(shù)值模擬的爆破地震效應(yīng)影響因素分析[D];長安大學(xué);2014年
4 田俊斌;低滲透煤巖體水力壓裂裂隙擴(kuò)展演化及其增透機(jī)理研究[D];太原理工大學(xué);2014年
5 孫麗;空氣間隔軸向不耦合裝藥預(yù)裂爆破數(shù)值模擬研究[D];中南大學(xué);2012年
6 王衛(wèi)超;煤體中爆炸應(yīng)力波及爆破作用的試驗(yàn)研究[D];河南理工大學(xué);2010年
7 王以賢;煤體爆破破碎機(jī)理的模擬試驗(yàn)研究[D];河南理工大學(xué);2009年
8 趙建博;風(fēng)口上置置換通風(fēng)機(jī)理及系統(tǒng)性能實(shí)驗(yàn)研究[D];西安建筑科技大學(xué);2007年
9 張翔;三峽電站主廠房分層空調(diào)技術(shù)的應(yīng)用研究[D];重慶大學(xué);2001年
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