HR: 1340h
AN: H53E-1470    [Abstracts]
TI: Comparing Pore-scale and Macro-scale Capillary Pressure Measurements Using a Two- dimensional Micromodel
AU: * Brown, K I
EM: brownke@engr.orst.edu
AF: School of Chemical, Biological and Environmental Engineering Oregon State University, 102 Gleeson Hall, Corvallis, OR 97330,
AU: Porter, M L
EM: porterma@engr.orst.edu
AF: School of Chemical, Biological and Environmental Engineering Oregon State University, 102 Gleeson Hall, Corvallis, OR 97330,
AU: Wildenschild, D
EM: dorthe@engr.orst.edu
AF: School of Chemical, Biological and Environmental Engineering Oregon State University, 102 Gleeson Hall, Corvallis, OR 97330,
AB: Capillary pressure plays a critical role in multiphase flow and transport in porous media. At the pore scale, capillary pressure is defined by Laplace's law which states that capillary pressure is a function of surface tension, contact angle and curvature. This study focuses on imaging and estimating pore scale properties that determine capillary pressure. Drainage and imbibition experiments for a NAPL-water system are conducted in a two-dimensional micro-scale porous medium. High resolution images of the phase distributions and associated interfaces within the pores are collected during the experiments. Images are taken at a rate of approximately 50 frames per second with a resolution between 1-10 ìm per pixel. In addition, the pressure in each phase is measured with a transducer outside the porous medium, and pressure-saturation curves are plotted from the data. We will attempt to use Laplace's Law to estimate the average pressure inside the porous medium based on measured curvatures. The two pressure values (measured outside the system versus calculated via Laplace's Law) will be compared. The images will allow for investigation of pore scale properties during dynamic flow conditions, as well as static conditions, and importantly, allow for comparison among the two situations. Specifically, relaxation of menisci interfaces and resulting changes in interface curvature, and thus capillary pressure, will be correlated to variations in system properties such as fluid-fluid viscosities and flow rates.
DE: 1831 Groundwater quality
DE: 1866 Soil moisture
DE: 1875 Vadose zone
SC: Hydrology [H]
MN: 2007 Fall Meeting