Patent ID: 7548840
Filing Date: 2009-06-16
Classification: G06F

Abstract:
1. A method for compositional reservoir simulation of fluid flow within a subterranean reservoir, the method comprising: (a) providing a model of a subterranean reservoir, the model having a grid defining a plurality of cells such that each cell is associated with fluid therewithin, the fluid residing in a vapor phase and a liquid phase; (b) selecting at least one cell of the plurality of cells that is associated with fluid residing in the vapor phase and with fluid residing in the liquid phase; (c) estimating which of the vapor phase and the liquid phase is present in a least abundant amount; (d) assigning the phase having the least abundant amount as the primary phase and assigning the other phase as the secondary phase; (e) computing phase properties of the primary phase responsive to primary variables associated with the primary phase and computing phase properties of the secondary phase utilizing mass balance and responsive to secondary variables associated with the secondary phase, such that stability is ensured while computing the phase properties of the secondary phase due to assigning the phase having the least abundant amount as the primary phase in step (d); and (f) outputting a visual display responsive to the computed phase properties of the primary phase and the computed phase properties of the secondary phase.