A new numerical coupling model of horizontal well completed with flow control method in bottom water reservoir

Key words:  bottom water reservoir  horizontal well  flow control completion  numerical simulation  coupling model  hybrid grid  pseudo conductivity

Abstract:

A new 3D hybrid grid model for oil-water two-phase was built, in which numerical simulation was carried out to forecast production performance of a bottom water reservoir with horizontal wells completed using a flow control technique. The new model consists of reservoir flow, wellbore flow and ICD pipe flow control models. A parameter of "pseudo conductivity" was defined in order to linearize the flow in wellbore and ICD pipe and to unify the mathematical expressions of all the three flow models, and then a system of linear equations coupling with the three flow models can be readily established and solved. The pseudo conductivity parameter is calculated as the ratio of the flow rate versus pressure drop for a certain fluid phase passing through adjacent grids by wellbore flow or the controlled flow through ICDs. The simulation results of a case study show that, the larger the flow resistance is, the smaller the pseudo conductivity will be, and vice versa. In comparison with the conventional open hole sand control completion method, the flow control method can greatly delay water breakthrough time by improving the performance of inflow and reducing the pressure drop in near wellbore region. The new model can provide a theoretical guidance for the design and application of the flow control completion method.