Modeling Method Of Braided River Architecture And Sensitivity Analysis Of Parameters

In order to research the geometry and the contact relationship of the architecture unit inside the reservoir,fine description is essential.Previous studies on fluvial reservoir architecture mainly focus on meandering river,while most studies on braided river reservoir architecture focus on bar level.Due to the limit of the technology and data,the quantitative description of the interlayer level inside the bar,especially the establishment of 3d model,is still being explored.In this paper,the geometry and contact relationship of the architecture unit in braided river reservoir are modeled,and the sensitivity analysis of the parameters affecting the fluid flow capacity are also carried out.The objected-based method is adopted to successively simulate the channel,the bar,and the interlayer,and the corresponding test and model optimization are carried out by adjusting parameters and rules.During parameter sensitivity analysis,orthogonal experimental design is adopted for research and analysis.Firstly,the levels of the factors affecting fluid flow capacity are determined.Then with the help of orthogonal design assistant ? V3.2 software,the proper orthogonal table is drawn.At the same time,the corresponding property models(porosity and permeability)are established based on the previously optimal model.Two groups of different well locations are set for reservoir numerical simulation,and corresponding cumulative oil production and water cut data are obtained.Finally,the experimental results are analyzed by means of visual analysis and variance analysis,and the factors that have the greatest influence on fluid flow capacity are determined.The main research results are as follows:(1)Fluvsim method is one of the objected-method,the principle of which is studied.Combined with the geometric features of each architecture unit of braided river reservoir,the objected-based method is adopted to successively simulate the channel,the bar,and the interlayer.Empirical data and formulae from modern sedimentation and outcrop statistical analysis are collated and used to constrain the parameter distribution range of each target body.Finally,a set of complete progressive modeling process is formed,and the patent of inventions is also applied.(2)Based on the generation of the above model,internal tests are conducted through the distribution style of each architecture unit(various preset modules)and the quantitative relationship of geometric parameters(width to thickness ratio,length to width ratio,etc.).At the same time,the contact modes of each architecture unit are also tested,and the model that best conforms to the geological model of braided river is selected.(3)The density and the length of interlayer,the difference of permeability between bar and interlayer,and the difference of permeability between bar and channel,are selected as the main factors affecting fluid flow capacity.Taking cumulative oil production and water cut as dynamic indexes,the experiment is carried out by using orthogonal test design method.The research shows that the significant factor affecting the fluid flow capacity is the difference of permeability between the bar and the interlayer.