Study On Numerical Simulation Of Cementing Displacement

The numerical simulation can carry out long-distance cementing displacement research and visually display the dynamic development process of cementing displacement interface.It has become an important research means of cementing displacement research.The optimization of calculation parameters can greatly improve the efficiency of numerical simulation.The optimization of calculation parameters has important theoretical and engineering value.Aiming at the problem of cementing displacement,considering the mass diffusion process of two kinds of displacement fluids,a numerical experimental model of twophase laminar flow cementing displacement is established based on the principle of relative motion.The calculation method of dynamic displacement interface length and displacement efficiency is defined,which provides a research means for cementing displacement research.Aiming at the problem of too long computer time for numerical simulation of cementing displacement,based on the theory that the short model of two-phase laminar flow cementing displacement numerical experiment is independent of calculation parameters,this paper studies the influence of space discrete step,time discrete step and iteration times on numerical simulation results,optimizes calculation parameters such as space discrete step and time step,and improves the efficiency of numerical simulation of cementing displacement.Finally,based on the results of short model mesh optimization,numerical simulation of 300 s cementing displacement process in 300 m long horizontal wells is carried out to study the influence of centrality,density contrast,fluid rheological parameters and flowrate on cementing displacement.It has theoretical guiding significance for cementing displacement design.