New upscaling technique for compositional reservoir simulations of miscible gas injection

The use of compositional reservoir simulation is necessary to better represent the physical phenomena associated with enhanced oil recovery methods, particularly with miscible or near-miscible gas injection processes. However, upscaling of the geological fine model is required because computational costs can make it unpractical to perform compositional simulations in fine-scale models. Therefore, upscaling of fine-scale geological models is important and the use of coarse-scale models in reservoir simulation is necessary to reduce computational time. However, it can degenerate results due to loss of resolution of the small-scale phenomena, averaging of sub-grid heterogeneity and numerical dispersion, especially in oil fields where miscible gas is injected, continuously or alternatively with water (WAG).