CAJ | 학술논문

针对国内外对双台阶水平井渗流规律及产能分析研究相对欠缺的情况，以水平井不稳定渗流模型为基础，根据势叠加原理，采用半解析方法建立了双台阶水平井不稳定渗流模型，同时考虑了井筒内变质量流动压降损失影响，给出了定压生产条件下耦合模型解法。通过实例计算，结果表明双台阶水平井比产能指数沿井筒长度不是均匀分布的，大致呈非对称“U”型分布，且跟端的比产能指数略高于趾端；井筒沿程压差分布曲线明显有一个台阶，说明压降损失主要集中在中间夹层连接段处，主要为重力压降损失。该成果为双台阶水平井井身结构设计，及合理利用双台阶水平井进行开发方案设计、计算开发指标、制订开发调整方案等提供理论依据，从而合理、高效地开发我国复杂油气田。
침대국내외대쌍태계수평정삼류규률급산능분석연구상대흠결적정황，이수평정불은정삼류모형위기출，근거세첩가원리，채용반해석방법건립료쌍태계수평정불은정삼류모형，동시고필료정통내변질량류동압강손실영향，급출료정압생산조건하우합모형해법。통과실례계산，결과표명쌍태계수평정비산능지수연정통장도불시균균분포적，대치정비대칭“U”형분포，차근단적비산능지수략고우지단；정통연정압차분포곡선명현유일개태계，설명압강손실주요집중재중간협층련접단처，주요위중력압강손실。해성과위쌍태계수평정정신결구설계，급합리이용쌍태계수평정진행개발방안설계、계산개발지표、제정개발조정방안등제공이론의거，종이합리、고효지개발아국복잡유기전。
The study of percolation theory and deliverability analysis for two-stepped horizontal well is imperfect at home and abroad. Based on the horizontal well unstable flow model and the potential superposition principle,the two-stepped horizontal well unstable flow model is established by using a semi-analytical method and by considering the variable mass flow within the wellbore pressure loss,the solution of the coupling model is presented under the bottomhole constant pressure. The research results of the real examples show that the productivity index distribution along the borehole is non-uniform,which is the asymmetric“U”shaped pattern. The productivity index at the heel is slightly higher than that at the toe. There is an obvious step on the curve of pressure difference distribution along the wellbore,which shows that the pressure loss at the connection section is larger. The results are meaningful and provide a theoretical basis for the two-stepped horizontal well casing design,and for designing the field development project,computing development indicators,formulating development adjustment programs, and therefore,to efficiently develop the complex oil and gas fields.