A model to calculate stress sensitivity is established based on theory of accumulation of geology, geomechanics and theory of flow through porous media. Compared with experimental results, the model is accurate and reliable. Distribution range of tight oil reservoir in Daqing Field is narrower than that of Changqing Field. It results in that stress sensitivity of Daqing Field is severer than that of Chaingqing Field. And productivity of Daqing Field is lower than that of Changqing Field. We make a quantitative description on mechanism of stress sensitivity in tight oil reservoirs.

Lattice Boltzmann multiphase method based on Shan-Chen model is used to a systematic study on dynamics of two-phase fluid flows in a lid-driven square cavity.Effects of Reynolds (Re),Capillary number (Ca) and surface wettability on flowing and mixing are investigated in details.It shows that the greater the Re and Ca,the longer pength of two phase fluid mixing interface in the cavity.In addition,the length of mixing interface increases with surface hydrophobicity.However,for a highly hydrophilic surface,the length of mixing interface tends to a constant finally.