页岩气藏水平井分段压裂渗流特征数值模拟

页岩气藏具有独特的存储和低渗透特征，其开采技术也有别于常规气藏的开采技术，水平井完井技术和分段压裂技术是成功开发页岩气藏的两大关键技术。水平井完井和分段压裂后形成的复杂裂缝网络体系以及吸附气的解吸作用等因素，都给页岩气井的渗流机理研究带来极大挑战。研究表明，利用数值模拟软件来模拟页岩气井的裂缝网络系统，不仅能模拟页岩气的渗流机理，也能为编制页岩气藏开发方案提供可靠的理论依据。因此以Eclipse2010.1数值模拟软件为研究平台，建立了３种考虑吸附气解吸的页岩气分段压裂水平井数值模型，能够模拟页岩气藏水平井的生产动态，对体积压裂后形成的裂缝参数进行优化模拟。结论认为：只有通过增加水平井的数量和储层改造体积（SRV）、选取异常高压区钻井和压裂出具有充分导流能力的裂缝，才能有效提高页岩气藏的采收率，实现页岩气藏的有效开发。

Numerical simulation of seepage flow characteristics of multi stage fracturing (MSF) in horizontal shale gas wells

Due to unique features of preservation and very low permeability, shale gas reservoirs necessitate the recovery technology distinct from that for conventional gas reservoirs. Horizontal well completion and multi stage fracturing (MSF) are two key technologies for successful shale gas reservoir development. But on the other hand, the resulted complex fracture network system and desorption of adsorbed gas constitute a great challenge to research on the seepage flow mechanism of MSF in shale gas wells. This study shows that the numerical simulation software can be adopted to simulate the said complex fracture system, with which not only can the system's seepage flow mechanism be simulated, but a reliable theoretical basis can be provided for formulating shale gas reservoir development plans. Therefore, with the Eclipse simulation 2010.1 as a research platform, the well numerical models considering the desorption of adsorbed gas were established to simulate the dynamic characteristics of horizontal shale gas wells and to optimize parameter simulation for fractures formed by high volume hydraulic fracturing (HVHF). Through analysis it is concluded that shale gas recovery efficiency will be improved and shale gas reservoirs will be effectively developed only by increasing the number and SRV (Stimulated Reservoir Volume) of horizontal wells, selecting abnormal pressure zones for boreholes, and creating adequately conductive fractures.