【作者】 孙华；

【导师】 李阳；

【作者基本信息】 中国石油大学 ， 油气田开发工程， 2008， 硕士

【摘要】 低渗透油气藏是我国重要的油气资源,其中特低渗透油藏的动用程度比较低。大量实验研究表明:低渗透油藏具有启动压力梯度和压力敏感性特征,其渗流过程为非线性渗流。为了更好的对特低渗透油藏进行开发,就要对其生产潜力进行评价,而目前的很多产能方程并不能完全适合该类油藏,本文首先根据特低渗透油藏的岩心实验结果分析了特低渗透油藏产能的影响因素,以低渗透油藏的渗流理论为基础,建立了完整的单相稳定渗流的数学模型,推导了考虑不同影响因素的特低渗透油藏的一维单向、平面径向、球面向心稳定渗流的产能解析公式。用同一个特低渗透油藏作为实例,结合推导出的产能公式进行计算,讨论并分析了各非线性因素对产能的影响,并对这些多因素影响下的三者的产能曲线进行了对比分析,证实了在相同的生产条件下,单向渗流更具有优越性。其次,本文从启动压力梯度和压力敏感性角度出发,给出了人工垂直裂缝井的稳态产能表达式,并分别考虑了渗透率各向同性和渗透率各向异性的情况,分析了裂缝、启动压力梯度、压敏效应等对产能的影响。再次,本文以特低渗透油藏的平面径向流为例推导了弹性采收率预测公式,并通过核算经济极限日产油量,确定出相应的采收率极限值预算,为这类油藏的开发提供了一定的指导意义。更多还原

【Abstract】 Low permeability reservoir plays an important role in our oil and gas resources,however, the development degree of super-low permeability reservoir is very low. Lots of experimental research has showed that the low permeability reservoir had the features of pressure sensitivity and threshold pressure gradient and there existed the nonlinear seepage during fluid flow. The potential productivity need evaluating for the better development of low permeability reservoir. However ,the productivity equation can not satisfy the demand of the reservoir at present. Firstly, the influencing factors of low permeability reservoir productivity were analyzed by the result of core flow test; a single phase and stable seepage numerical model has been established based on the percolation theory of low permeability reservoir and the productivity analytical formulas of 1-D plane radial and spherical seepage were derived considering the different influence factors. The influence of nonlinear factors on productivity was discussed and analyzed through the calculation on the same low permeability reservoir example with the derived productivity analytical formulas. It was demonstrated that the single phase seepage had the advantage by the comparison of different productivity curves in the same condition. Secondly, starting from the features of pressure-sensitivity and threshold pressure gradient, the stable productivity expression of artificial vertically fractured well was obtained and the influence of fracture, threshold pressure gradient and pressure-sensitivity on productivity was analysed in permeability isotropic and permeability anisotropic formations. At last, the elastic oil recovery prediction formula was deduced taking the plane radial seepage of super-low permeability reservoir as example and the limit value budget was gained by the account economic ultimate oil output correspondingly, which had the guiding significance on the development of low permeability reservoir at some extent.更多还原