Present Situation Research on Axial Flow Displacement Theory During Cementing

Abstract

It is well known that displacing drilling fluid effectively is the premise to obtain good cementing quality. During cementing axial flow is the major way to displace annular drilling fluid. So we put emphasis on the research of axial flow displacement theory. At present axial flow displacement theory mainly focuses on three aspects: displacement theory study based on wall shear stress; displacement theory study based on the numerical simulation technique for the displacement interface stability; displacement theory study based on laboratory experiments. In this paper, we analyzes the present research situation and their respective advantages and defects of the above mentioned three aspects in displacement theory. We put forward that infinitesimal mechanical analysis for displacement interface and numerical simulation technology for the interface stability should combine organically. In order to achieve good cementing effect, we should stress on the research and measurement of profile displacement efficiency and put the interface moving steadily as a prerequisite. As a result, our research can lay a fundamental the future development of axial flow displacement theory. Key words: Axial flow; Displacement theory; Wall shear stress; Interface stability; Displacement efficiency