本文關(guān)鍵詞： 瓦斯運移 數(shù)值模擬 瓦斯抽采 流固耦合 瓦斯壓力　出處：《遼寧工程技術(shù)大學(xué)》2013年碩士論文　論文類型：學(xué)位論文

【摘要】：近年來隨著煤礦井下開采深度的增加和開采強度的增大,煤層瓦斯涌出強度也越來越大,嚴(yán)重制約著礦井生產(chǎn),對于高瓦斯礦井這種問題表現(xiàn)的更為突出。礦井瓦斯抽采已成為瓦斯災(zāi)害防治的重要手段,同時瓦斯作為一種清潔高效的能源資源,如果能夠最大限度的將煤層瓦斯采出并加以利用,可以變害為寶為人類造福。依據(jù)煤礦安全規(guī)程,對高瓦斯有煤與瓦斯突出危險的煤層在回采前,必須進行預(yù)抽,而如何確保瓦斯抽采效果,合理的布置鉆孔,一直是個難題,目前多通過現(xiàn)場實測的辦法,來估算抽采布置間距,該方法需要布置多組實驗鉆孔且需較長的抽采觀測時間。 本文基于本煤層瓦斯抽采方法選擇及抽采鉆孔布置問題,將煤巖體視為具有孔隙裂隙的雙重介質(zhì)結(jié)構(gòu),考慮由于瓦斯壓力下降引起的孔隙結(jié)構(gòu)的變形,從微觀到宏觀,逐步研究了煤層瓦斯的儲存特征和滲流特征,在達西定律、菲克第一定律、連續(xù)性方程和輔助方程的基礎(chǔ)上,以煤巖體體積應(yīng)變?yōu)轳詈厦浇榻⒘丝紤]裂隙滲流、微孔隙擴散和煤巖體變形的耦合滲流場方程。借助于大型數(shù)值分析軟件對建立的數(shù)值模型進行分析求解,并根據(jù)沙曲礦4煤層實際的瓦斯賦存條件,分別建立平面應(yīng)變模型和三維幾何模型,分析單孔和孔群抽采時煤層瓦斯壓力、達西速度、滲透率等參數(shù)隨抽采時間的變化規(guī)律,以及工作面傾向順層鉆孔抽采、工作面傾向傾斜順層鉆孔抽采和工作面扇形順層鉆孔抽采三種不同的順層鉆孔瓦斯抽采方法的抽采效果,研究了鉆孔布置間距、夾角等參數(shù)對抽采效果的影響。 研究結(jié)果表明：距離抽采鉆孔較近位置瓦斯壓降呈“L”型,較遠位置呈反“S”型,隨距離抽采位置增大,壓降曲線逐漸由“L”型轉(zhuǎn)為反“S”型；滲流速度隨抽采時間變化呈三個階段,抽采一周左右滲流速度達峰值,隨后快速下降,抽采穩(wěn)定后緩慢下降；工作面傾向順層抽采與傾斜順層抽采、扇形順層三種抽采方法比較,相同時間傾向順層抽采瓦斯壓力降低較快,傾向傾斜抽采存在兩個抽采區(qū)域瓦斯壓力降低緩慢；扇形順層抽采時,以施鉆位置為中心,影響范圍呈扇形輻射狀發(fā)展,隨距施鉆中心位置增大,瓦斯壓力下降速度減�。汇@孔布置密度對扇形順層鉆孔瓦斯抽采的效果影響比較顯著。
[Abstract]:In recent years, with the increase of mining depth and mining intensity, the intensity of coal seam gas emission is increasing, which seriously restricts the mine production. Gas drainage has become an important means of gas disaster prevention and control, and gas is a clean and efficient energy resource. If the coal seam gas can be extracted and utilized to the maximum extent, it can be turned into a treasure for the benefit of mankind. According to the coal mine safety regulations, the coal seam with high gas and dangerous gas outburst must be pre-drained before mining. However, how to ensure the gas drainage effect and how to arrange the boreholes reasonably is always a difficult problem. At present, the spacing of the drainage arrangement is estimated by the method of field measurement, which needs to arrange many experimental boreholes and take a long time to observe the drainage. Based on the selection of coal seam gas drainage method and the layout of drainage borehole, the coal and rock mass is regarded as a dual medium structure with pore fissure, and the deformation of pore structure caused by gas pressure drop is considered, from micro to macro. The storage and seepage characteristics of coal seam gas are studied step by step. On the basis of Darcy's law, Fick's first law, continuity equation and auxiliary equation, the fracture seepage is established with the volume strain of coal and rock mass as the coupling medium. The coupled seepage field equation of micro-pore diffusion and coal and rock mass deformation is analyzed and solved by means of large-scale numerical analysis software, and according to the actual gas storage conditions of No. 4 coal seam in Shaqu Coal Mine, the numerical model is analyzed and solved. The plane strain model and 3D geometric model are established respectively to analyze the variation of gas pressure, Darcy velocity, permeability and other parameters of coal seam during single hole and hole extraction. The effects of three different methods of gas extraction from inclined seam drilling and sector bedding drilling are studied. The influence of the parameters such as the spacing of borehole arrangement and the angle between the boreholes on the extraction effect is studied. The results show that the gas pressure drop is of "L" type near the borehole, and the "S" type is opposite in the distance. The pressure drop curve gradually changes from "L" type to "S" type with the increase of the distance extraction position, and the seepage velocity varies in three stages with the extraction time. The percolation velocity reaches the peak value in about a week of extraction, then decreases rapidly, and then decreases slowly after the stability of extraction. At the same time, the gas pressure decreases rapidly in the down-bed drainage, and the gas pressure decreases slowly in two drainage areas in inclined inclined drainage, and the influence range develops in the shape of fan-shaped radiation with the drilling position as the center, and the gas pressure decreases slowly in the two drainage areas in the inclined inclined drainage, and in the same time, the gas pressure decreases slowly in two drainage areas. With the increase of the location of the drilling center, the gas pressure decreases, and the borehole layout density has a significant effect on the effect of gas extraction.
【學(xué)位授予單位】：遼寧工程技術(shù)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2013
【分類號】：TD712

【參考文獻】

相關(guān)期刊論文 前10條

1 麻翠杰,郭大浩,鄧英爾,黃潤秋,劉慈群;致密煤層氣運移的數(shù)值模擬[J];大慶石油學(xué)院學(xué)報;2005年03期

2 余楚新,鮮學(xué)福,譚學(xué)術(shù);煤層瓦斯流動理論及滲流控制方程的研究[J];重慶大學(xué)學(xué)報(自然科學(xué)版);1989年05期

3 許江,鮮學(xué)福,杜云貴,張廣洋;含瓦斯煤的力學(xué)特性的實驗分析[J];重慶大學(xué)學(xué)報(自然科學(xué)版);1993年05期

4 聶百勝,王恩元,郭勇義,吳世躍,衛(wèi)建鋒;煤粒瓦斯擴散的數(shù)學(xué)物理模型[J];遼寧工程技術(shù)大學(xué)學(xué)報(自然科學(xué)版);1999年06期

5 孫可明,梁冰,王錦山;煤層氣開采中兩相流階段的流固耦合滲流[J];遼寧工程技術(shù)大學(xué)學(xué)報(自然科學(xué)版);2001年01期

6 劉建軍,劉先貴;煤儲層流固耦合滲流的數(shù)學(xué)模型[J];焦作工學(xué)院學(xué)報;1999年06期

7 魏凱豐;宋少英;張作群;;天然氣混合氣體粘度和雷諾數(shù)計算研究[J];計量學(xué)報;2008年03期

8 謝生榮;武華太;趙耀江;何富連;郭海東;袁勝軍;;高瓦斯煤層群“煤與瓦斯共采”技術(shù)研究[J];采礦與安全工程學(xué)報;2009年02期

9 梁冰;陳天宇;孫維吉;張春梅;姜勇;;侵入巖對煤層氣區(qū)塊產(chǎn)能影響的仿真研究[J];采礦與安全工程學(xué)報;2010年02期

10 孫培德;;煤層瓦斯流場流動規(guī)律的研究[J];煤炭學(xué)報;1987年04期

相關(guān)博士學(xué)位論文 前1條

1 劉洪永;遠程采動煤巖體變形與卸壓瓦斯流動氣固耦合動力學(xué)模型及其應(yīng)用研究[D];中國礦業(yè)大學(xué);2010年

，

本文編號：1531730