Effects Of Low Permeability Reservoir Effect On The End Face Of Seepage

In-depth understanding of low permeability reservoir pore structure characteristics and flow characteristics,how cost-effective development of low permeability oil field has important guiding significance.In this paper,the use of advanced controlled mercury analyzer for low permeability reservoir pore structure were studied.The experimental results showed that: low permeability,ultra-low permeability reservoir flow capacity at the micro control mainly by the throat,regardless of pore size;the average throat radius and mainstream throat radius reservoir seepage ability to reflect differences in the average throat radius and mainstream throat radius of Xinjiang and Changing area caused by low permeability reservoir of Xinjiang and Changing different percolation decisive factor;determinants of seepage ability not only has an average throat radius size,shape throat size distribution also determines the effective flow capacity of the reservoir;unlike in high permeability reservoirs,microscopic heterogeneity of low permeability reservoir the presence of such a large throat provide high flow capacity,it is conducive to the development of the reservoir.Core grinding process will be clogging the core end face,the end face of the blockage will reduce permeability and permeability reduction will increase the driving pressure,the pressure loss of the fluid flow will increase,namely core end surface effect,also known as core skin effect.Core epidermis showed contamination with oil well completions occurred during the near wellbore in actual field production problems.In low permeability core flow experiments,since the boundary properties of liquids abnormal,non-Newtonian fluids or rock channel complexity,the law no longer meets its liquidity classic Darcy's law.Only when the displacement pressure is greater than a certain value that is activated when the pressure gradient,the fluid flow can occur.Experimental results show that the lower the core permeability,displacing the fluid velocity relative to the faster,the higher the relative viscosity of the flooding,the impact on the end face of the effects of low permeability reservoir seepage law of the more remarkable.