According to the research theory of improved black oil simulator,a practical mathematical model for CO2 miscible flooding was presented.In the model,the miscible process simulation was realized by adjusting oil/gas relative permeability and effective viscosity under the condition of miscible flow.In order to predict the production performancefast,streamline method is employed to solve this model as an alternative to traditional finitedifference methods.Based on streamline distribution of steady-state flow through porous media with complex boundary confirmed with the boundary element method(BEM),an explicit total variation diminishing(TVD)method is used to solve the one-dimensional flow problem.At the same time,influences of development scheme,solvent slug size,and injection periods on CO2 drive recovery are discussed.The model has the advantages of lessinformation need,fast calculation,and adaptation to calculate CO2 drive performance of all kinds of patterns in a random shaped porous media with assembly boundary.It can be aneffective tool for early stage screening and reservoir dynamic management of the CO2miscible oil field.