Numerical Simulation of Cementing Displacement Efficiency of Rotating Liner

In recent years, rotating liner cementing technology has been widely used in China. It is necessary to study the efficiency of cementing displacement under the condition of rotating liner. A numerical simulation method for cementing displacement of rotating liner was established by using fluid dynamics software Fluent, and numerical experiments were carried out for different rotating speed coupling fluid performance, displacement velocity and liner displacement efficiency. The results show that the drilling fluid trapped in the narrow edge of annulus is displaced by the annulus spiral flow under the action of liner rotation, and the higher the rotational speed, the higher the displacement efficiency. Under the conditions of different liner rotation speed, the change rules of cementing displacement efficiency with fluid density difference, liner concentration, rheological properties of cement slurry and displacement velocity are basically similar. The ideal displacement effect can be obtained by using the combination of cement slurry and drilling fluid with low density difference and the appropriate liner concentration. Reducing the viscosity coefficient and fluidity index of cement slurry or using low speed laminar flow and high speed turbulent flow can improve the displacement effect. The results are helpful to improve the displacement efficiency of liner rotary cementing and provide a theoretical basis for the optimization of cementing operation scheme.