固体颗粒表面吸附水层厚度实验研究

以玻璃微珠为对象，探索堆积固体颗粒表面吸附水层厚度随驱动压力梯度的变化规律。结果表明：完全浸润的堆积固体颗粒之间存在3种不同性质的水，因其受表面作用力的大小不同，可用离心法加以区分。随着离心力的增加，依次驱替出自由水、毛管水和吸附水层水。结合重量分析，用离心法可得到不同驱动压力梯度下的吸附水量及吸附水层厚度。吸附水层厚度是水动力学条件的函数，其随驱动压力梯度的变化规律为解释多孔介质中水相的渗流特性提供依据。

EXPERIMENTAL STUDY OF ADSORDED WATER LAYER ON SOLID PARTICLE SURFACE

The purpose of this paper is to investigate experimentally the changing regularity about the thickness of adsorbed water layer on solid particle with driving gradient pressure by using micro-glass ball. There are three types of water existing among packed solid particles, which can be distinguished by using the centrifugal method. Free water can be removed under lower driving gradient pressure. Capillary water maybe removed by increasing the rotating rate, i.e., the increase of driving gradient pressure. Owing to the strong adsorption interaction between water molecule and the surface of solid particle, the adsorbed water on surface couldn't be removed easily, which needs higher driving gradient pressure. In combination with the gravimetric method, one can obtain the adsorption amount of water and the thickness of adsorbed water layer on solid surface under various driving gradient pressures. The thickness of the adsorbed water layer is a function of hydrodynamics. It is of advantage to interpret the percolation behavior in low permeability reservoir using the changing rule of adsorbed water layer with driving gradient pressure.