ESTIMATION OF CAPILLARY-PRESSURE AND RELATIVE PERMEABILITY FUNCTIONS FROM CENTRIFUGE EXPERIMENTS

A method to estimate capillary pressure and relative permeability curv es simultaneously from transient, multirate centrifuge experiments per formed on homogeneous rock is presented. The unknown functions are rep resented with B-splines, and the number of knots and coefficient value s are selected through a regression-based procedure. The method is dem onstrated by use of experimental data for dolomite and sandstone sampl es with air/water and oil/water fluid systems. An analysis of the accu racy of the estimates is presented. The capillary pressure curve and r egions of both relative permeability curves can be estimated accuratel y.