Comparison of two volume balance fully implicit approaches in conjunction with unstructured grids for compositional reservoir simulation

Development of an embedded discrete fracture model for 2D and 3D unstructured grids using an element-based finite volume method

“…The EbFVM is a general approach that can be applied to both 2D and 3D unstructured grids. Because of its flexibility in the discretization of the domain and convenience of implementation in simulators that can construct arbitrary connections between gridblocks, this approach was implemented in UTCOMP-RS, an in-house, multi-component reservoir simulator for both two-and three-dimensional simulations (Marcondes and Sepehrnoori, 2010;Marcondes et al, 2013;Araújo et al, 2016;Fernandes et al, 2016). The simulator uses an implicit-pressure, explicit-composition (IMPEC) formulation.…”

“…Unstructured grids have been used in reservoir simulation to represent geologically complex reservoirs (Fung et al, 1992;Durlofsky and Chien, 1993;Verma and Aziz, 1997;Prévost et al, 2002Prévost et al, , 2005Edwards, 2002;Hoteit and Firoozabadi, 2006a;Vitel and Souche, 2007;Sepehrnoori, 2007, 2010;Araújo et al, 2016;Fernandes et al 2016Fernandes et al , 2017Samier and Masson, 2017). In comparison with structured grids, unstructured grids are more capable of representing irregular reservoir structures and reservoir boundaries, as they provide more flexibility regarding the geometry of gridblocks and their discretization.…”

Development of a fully implicit approach with intensive variables for compositional reservoir simulation

“…Therefore, derivatives of the phase composition and phase mole fraction with respect to the number of moles of each component and pressure are required. The procedure that follows is based on the works of Subramanian et al (1987) and Wong et al (1987) and has been implemented by Fernandes (2014) and Fernandes et al (2016).…”

“…Later, Fernandes et al (2015b) performed similar study for unstructured grids using the Element based Finite Volume Method (EbFVM) (Baliga and Patankar, 1983;Marcondes and Sepehrnoori, 2010). Fernandes (2014) and Fernandes et al (2016) presented and implemented a FI version of the formulation proposed by Acs et al (1985) and compared it to the formulation of Collins et al (1992). Also, Fernandes et al (2017) implemented the Coats formulation in UTCOMPRS.…”

A TVD scheme for 3d unstructured grids applied to compositional reservoir simulation

“…Additionally, IMPSAT (Implicit Pressure and Saturations) approaches (Fernandes et al, 2014;Fernandes et. al., 2015b) and two volume balance based fully implicit approaches (Fernandes, 2014;Fernandes et al, 2016) were implemented for both Cartesian and unstructured grids. In this manuscript, only IMPEC will be considered.…”