CAJ | 학술논문

为了综合反映启动压力和应力敏感对低渗透油藏开发规律的影响，首先，通过室内实验研究低渗透岩芯启动压力梯度和应力敏感效应，并建立启动压力梯度和动态渗透率的动力学模型；在此基础上，根据质量守恒定律和渗流力学理论，建立同时考虑启动压力和应力敏感效应的低渗透油藏油水两相渗流数学模型，据此研制低渗透油藏水驱数值模拟软件；然后，利用该软件研究不同特征对渗流场、开发规律的影响以及启动压力和应力敏感对开发效果的影响；最后，研究超前注水、增大注采比、增大注采速度对采收率的影响规律，并优化最佳注入参数。研究结果表明，启动压力梯度是低渗透油藏采收率较低的直接原因，应力敏感通过强化启动压力梯度的方式间接影响采收率；超前注水、增大注采比和增大注采速度均可以提高低渗透油藏采收率，提高幅度为：超前注水＞增大注采比＞增大注采速度；最佳超前注水时间为100 d，最佳注采比为1.1∶1，最佳注入速度为0.00015～0.00025 PV/d。
위료종합반영계동압력화응력민감대저삼투유장개발규률적영향，수선，통과실내실험연구저삼투암심계동압력제도화응력민감효응，병건립계동압력제도화동태삼투솔적동역학모형；재차기출상，근거질량수항정률화삼류역학이론，건립동시고필계동압력화응력민감효응적저삼투유장유수량상삼류수학모형，거차연제저삼투유장수구수치모의연건；연후，이용해연건연구불동특정대삼류장、개발규률적영향이급계동압력화응력민감대개발효과적영향；최후，연구초전주수、증대주채비、증대주채속도대채수솔적영향규률，병우화최가주입삼수。연구결과표명，계동압력제도시저삼투유장채수솔교저적직접원인，응력민감통과강화계동압력제도적방식간접영향채수솔；초전주수、증대주채비화증대주채속도균가이제고저삼투유장채수솔，제고폭도위：초전주수＞증대주채비＞증대주채속도；최가초전주수시간위100 d，최가주채비위1.1∶1，최가주입속도위0.00015～0.00025 PV/d。
In order to reflect the influences of starting pressure and stress sensitivity on the development law of low-permeability reservoirs,the following researches are conducted. Firstly,the dynamics models of threshold pressure gradient and dynamic permeability are established based on the experimental results of threshold pressure gradient and stress sensitivity effects. Based on this,the mathematical model of water-flooding in low-permeability reservoir with considering the starting pressure and stress sensitivity is established according to the law of conservation of mass and permeation fluid mechanics theories. Also,the corresponding numerical simulation software is developed. Then,the software is used to study the influences of different features on the seepage field and development law,and the effects of starting pressure and stress sensitivity on development effect. At last,the influences of advanced water flooding,increasing injection-production ratio and increasing injection-production rate on recovery are investigated by numerical simulation method. Simultaneously,the best injection parameter is optimized. The results show that:(1) Threshold pressure gradient directly results in the lower recovery of low-permeability reservoirs. Stress sensitivity indirectly affects the recovery by increasing the threshold pressure gradient. (2) All the measures of advanced water flooding,increasing injection-production ratio and increasing injection-production rate can enhance oil recovery of low-permeability reservoirs. And the order of the enhancing extent is:advanced water flooding>increasing injection-production ratio>increasing injection-production rate. (3) The optimal time of advanced water flooding is 100 d,the optimal value of injection-production ratio is 1.1∶1, and the optimal value of injection-production rate is 0.000 15~0.000 25 PV/d.