【作者】 张亚蒲；

【导师】 刘先贵；

【作者基本信息】 中国科学院研究生院（渗流流体力学研究所） ， 流体力学， 2006， 硕士

【摘要】 定向羽状水平井和直井压裂是两种有效的煤层气增产措施。本文采用数值模拟的方法为这两种增产措施开采方案的设计提供了理论依据和指导方案。围绕这一研究内容完成了以下工作： 1、本论文首先完善了渗流所编制的煤层气定向羽状水平井数值模拟软件，并利用该软件对已打羽状水平井进行产量模拟及预测，验证了软件的可靠性。 2、对比分析了羽状水平井和直井压裂增产效果以及地层压力变化的情况，得出了定向羽状水平井的增产机理。定向羽状水平井的分支在地层中广泛均匀延伸，使地层压力均匀、快速下降，增大了气体解吸扩散的机会，使被动用的区域大大增加，从而促使煤层气产量大大提高。 3、通过分析储层参数及井身结构参数对产气量的影响，提出了选区评价的重要依据以及井身结构优化的方法。分支呈非对称、发散均匀分布的多个主支的井身结构产气效果较好；渗透率、储层压力等储层参数是影响产气效果的重要因素。 4、建立了反映煤层气藏各向异性严重特点的地质模型，分析了各向异性对产能的影响，提供了直井压裂井网部署方案的设计方法及思路。 5、分析了压裂参数对产能的影响，当渗透率和裂缝长度一定时，累积产量并不是随导流能力的增大而线性增加。储层渗透率越低，采用直井压裂措施相对增产倍数越大。更多还原

【Abstract】 Pinnate horizontal multilateral well and vertical well fracturing are efficient technology which can increase coalbed gas recovery rate. In this dissertation, the numerical simulation technique is used providing necessary theory basis and guidance scheme for the implement of these two technology. The main research as follows:1 、 The software of Pinnate horizontal multilateral well is consummated. With a coalbed gas Pinnate horizontal multilateral well as an example, the productivity is forecasted. It is proved that the software is suitable for numerical simulation.2、 The effect of increase and the stratum pressure is compared between the pinnate horizontal multilateral well and the vertical hydraulic fracturing well. The main lateral and side laterals extending widely in stratum makes the stratum pressure drow down rapidly and uniformly in controlled area, which facilitates the desorption and diffusion of adsorbed gas.3 、 The effect of formation parameters and wellbore structures parameters on the gas production rate of pinnater horizontal multilateral well are analyzed. We gain the according of electing and evaluating good reservoir and the priciples on designing wellbore structure. The recovery effectiveness of multi-main lateral distributing uniformly is superior to single main lateral. There exists the optimal value of space between side laterals. The formation parameters are the prime factor which can effect the gas production.4、 The geological model is developed which can effect the heterogeneous reservoir characteristic. The effect of heterogeneous on the gas production is analyzed. The method of更多还原