Journal issues: 2/2001
11 December, 2001
CALCULATION OF RELATIVE PERMEABILITY FROM DISPLACEMENT TEST DATA
In the porous reservoir-rocks for the description and simulation of the two-phase flows the phase/relative permeability data and functions of fluids are necessary. The function of relative permeability is given generally depending on the degree of saturation of the wetting phase, and this function is determined in the most cases on the basis of data taken from laboratory displacement tests performed on rock-samples. Displacement tests can be carried out through a relatively short time, but the evaluation of the data received can be considered as a highly complex job. During displacement measurement the processing of data is made difficult by the unfavorable capillary end-effect appearing on the inlet and outlet of the sample unless the displacement has been made by a great speed, because then the value of the end effect shall have been minimized. Numerous methods are known to evaluate the data of displacement on an appropriately big speed, these often apply an auxiliary graphic method, and in other cases some empirical auxiliary functions will be applied. The analytic method elaborated and developed by the Authors offers a possibility to describe the permeability functions more accurately almost semi-analytically, and to calculate these from the data of displacement.