中文摘要：

低渗透油藏存在显著的应力敏感效应和启动压力梯度。流固耦合法对于高温、高压条件下岩石本构特性的确定和岩石物性参数的选取以及初始应力场的确定方面，均存在很大不确定性，加之其求解过程复杂，程序编制困难，实际应用存在很大问题。根据模拟软件中应力敏感处理方法和非达西渗流线性化原理，提出了数值模拟中应力敏感效应和启动压力梯度处理方法和依据。应用本方法对文东低渗砂岩油藏某区块进行了模拟研究。分别模拟考虑应力敏感和启动高压力梯度、不考虑应力敏感和启动高压力梯度（常规模型）、仅考虑应力敏感、仅考虑启动压力梯度对应的油田日产油量、累计产油量、采出程度的关系曲线。数值模拟结果表明：考虑应力敏感和启动压力梯度模型单井日产量较常规模型低，特别是投产初期；考虑应力敏感和启动压力梯度模型累计产油量和采出程度远低于常规模型。

英文摘要：

Stress sensibility and start-up pressure gradient lie in low permeability reservoir.Fluid-solid coupling method has large uncertainty on the aspects of determining rock constitutive behavior,choosing rock physical property parameters and recognizing initial stress field at high temperature and pressure.It has more problems in actual application for complex solution and difficult program programming.Based on the stress sensibility treating method in the numerical simulation software and the non-Darcy flow linearization theory ,a method was proposed which can be used to consider stress sensibility and start-up pressure gradient in the commercial numerical simulation software.It was applied in certain block of Wendong low-permeability sandstone reservoir.The relation curves of daily oil production,cumulative oil production and degree of reserve recovery were simulated under the condition of considering stress sensibility and start-up pressure gradient or not.The result indicates that the daily oil production is lower by the model considering stress sensibility and start-up pressure gradient than that by the ordinary model,especially at early stage of putting into production;the cumulative oil production and degree of reserve recovery by the model considering stress sensibility and start-up pressure gradient are much lower than that by the ordinary model.