Experimental Investigation of Hysteretic Dynamic Capillarity Effect in Unsaturated Flow.

ABSTRACT: The difference between average pressures of two immiscible fluids is commonly assumed to be the same as macroscopic capillary pressure, which is considered to be a function of saturation only. However, under transient conditions, a dependence of this pressure difference on the time rate of saturation change has been observed by many researchers. This is commonly referred to as dynamic capillarity effect. As a first-order approximation, the dynamic term is assumed to be linearly dependent on the time rate of change of saturation, through a material coefficient denoted by τ. In this study, a series of laboratory experiments were carried out to quantify the dynamic capillarity effect in an unsaturated sandy soil. Primary, main, and scanning drainage experiments, under both static and d

SUBMITTER: Zhuang L 

PROVIDER: S-EPMC5765445 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature