LBM Simulation Of Fluid Flow In Tight Reservoirs

The oil and gas exploration and development in the whole world are developing from conventional field to unconventional field.And the development of shale gas and tight oil become the hot spot of the industry,also deeply affects the pace of progress of the world.While unconventional oil and gas resource is abundant in our country and need to be developed.Unconventional reservoirs are mainly tight reservoirs,and there are significant differences compared with conventional reservoir,for example,the flow pattern,flow mechanics and so on.There are many related theory needs to be perfected.After decades of development,the lattice Boltzmann method has been proved to be reliable in the micro-scale flow.So in this paper,based on the lattice Boltzmann method,the mechanism of shale gas and tight oil are studied in order to better understand the flow and transport in the tight formation.Firstly,the basic principle of lattice Boltzmann method and model is introduced,and the correctness of the lattice Boltzmann model in this paper is verified by examples.And the difference between microscale gas flow model and conventional lattice Boltzmann model is put forward.Then,we study the gas flow in the microscale channel and gas flow in the microscale porous medium composed of cylindrical.And we prove the slip phenomenon in the microscale gas flow.Based on the research,we first study the flow pattern of the shale gas in shale reservoir,and then we simulate the shale gas flow in the nano-slit using the lattice Boltzmann method,also the permeability of the nano-slit is compared with the existing model.The shale porous medium is built based on the process method,and we simulate the shale gas flow in the porous media.For tight oil flow in the tight reservoir,based on the results of molecular dynamics simulation,we simulate the tight oil flow in the nano-slit by using Boltzmann method,and the results are compared and verified with the results of molecular dynamics.Later,based on five kinds of rough unit,the influence of surface roughness to the flow of tight oil is studied,and the effect of different rough unit to the flow is compared.