STOCHASTIC-ANALYSIS OF 3-PHASE FLOW IN HETEROGENEOUS POROUS-MEDIA .1.SPECTRA PERTURBATION APPROACH/

Stochastic analysis of steady state three-phase (water, oil, and air) flow in heterogeneous porous media was performed using the perturbatio n theory and spectral representation technique. The governing equation s describing flow of water, oil, and air are coupled and nonlinear. Th e key stochastic input Variables are intrinsic permeability, k, and th e soil grain size distribution index, alpha. Three different stochasti c combinations of these two input parameters were considered in the an alysis. The spectral/perturbation approach was used to develop closed- form expressions to describe stochastic variability of key output proc esses, such as capillary and individual phase pressures. The second pa per of this two-part series [Abdin and Kaluarachchi, this issue] will discuss the applicability and the validity of the spectral/perturbatio n technique to study the stochastic behavior of three-phase flow using numerical simulations.