Abstract
The main objective of this work is to study the drainage and imbibition in a capillary tube of circular section in a dimensionless form. First, we have presented the configuration of the studied problem. Equations governing physical problems and methods of resolution are displayed. Second, it demonstrates the dimensionless evolution of the interface and gas pressure as a function of non-dimensional time. Finally, the effect of gravity, the effect of inertia and the influence of gas compressibility and capillary radius are also presented and analyzed.