1. A method comprising: receiving fluid saturation data for fluid saturation parameters associated with permeabilities of a multidimensional spatial model of a geologic environment; adjusting at least a portion of the fluid saturation data to provide adjusted fluid saturation data by optimizing a quadratic function subject to linear constraints; and simulating flow of fluid using the adjusted fluid saturation data for fluid saturation parameters associated with permeabilities and the multidimensional spatial model of the geologic environment.