Experimental Study On Cement Displacement Efficiency Of Horizontal Well Injection

There are lots of technical and operational difficulties for cementing horizontal wells, and the displacement efficiency directly affects the level of cementing quality. So. improving the displacement efficiency becomes an important research direction to raise cementing quality of horizontal wells.This paper systematically analyses the factors affecting the displacement efficiency of cementing horizontal wells and determines the relevant simulation parameters of apparatus that is designed to simulate the process of cementing. A set of indoor displacement-efficiency-simulating-apparatus is established, which is easy to be adjusted in many features and can be used to study the flow conditions under the different deviation. Due to the complexity of the fluid" flow in the horizontal annular, some ordinary methods are difficult to study the flow distribution of horizontal annular. However, PIV (Particle Image Velocimetry) can not only show the physical form of flow field, but also provide the quantitative information of instantaneous flow. So the combination of displacement-efficiency-simulating-apparatus with the PIV can be applied to study the flow rule of horizontal annular, as well as real-time measurement of the displacement process.The flow rule of Power-Law fluid under different casing eccentricity, annular velocity and fluid properties was studied by applying the velocity distribution and flow velocity contour under different conditions. The effect that casing eccentricity, annular velocity, fluid performance has on the axial velocity distribution is analyzed by comparison and the variation rule of the axial velocity distribution under different conditions is gained. On the basis of experiments and analysis above-a series of displacement experiments of similar fluid in horizontal annular are carried out. Then compare the experimental results with that of the single fluid flow and summarize the effects of influence factors of displacement efficiency on the displacement process for cementing horizontal well.In this paper, PIV is applied to do systematic experiments in the research of flow rule of horizontal annular, and it is applied to study the displacement efficiency for the first time. The experimental results also show that the method is feasible and reasonable. The displacement experiments of similar fluid in the horizontal annular provide the study of displacement efficiency with a good research idea and reference.