Distinguished Author Series articles are general, descriptive representations that summarize the state of the art in an area of technology by describing recent developments for readers who are not specialists in the topics discussed. Written by individuals recognized as experts in the area, these articles provide key references to more definitive work and present specific details only to illustrate the technology. Purpose: to inform the general readership of recent advances in various areas of petroleum engineering.
Abstract
In this article, we present a high-level description of streamline-based flow simulation and focus on four areas in which the technology has proved valuable: reservoir-flow surveillance, flow simulation, history matching, and flood management. We highlight the advantages and disadvantages of streamline simulation (SLS) throughout the article and conclude with a look at possible SLS evolution. SLS re-emerged in the early 1990s to alleviate some computational problems faced by finite-difference (FD) simulation when confronted with high-resolution geological models characterized by heterogeneous spatial distributions of static properties. Since then, development and application of SLS has advanced the technology significantly, such that SLS complements conventional-modeling approaches in many reservoir-engineering (RE) workflows.
What Is SLS?
A streamline is defined as a line that is everywhere tangent to the local velocity field at a given instant in time. The smoke lines generated in a wind tunnel and shown in advertisements to demonstrate aerodynamic qualities of cars are a good representation of streamlines under the assumption of steady state.
Modern SLS used in the oil and gas industry has its roots in the analytical and semianalytical streamline and streamtube methods that date back to the work of Muskat and Wyckoff (1934). Since then, important early contributions were made by several authors (see Datta-Gupta and King 2007 for a reference list). Streamlines also have a long history in the areas of fluid mechanics and groundwater flow, and petroleum literature has drawn heavily from those sources.
In contrast to the early semianalytical streamtube work of the 1970s and 1980s, modern SLS generally is understood to be associated with work published after 1990 and is characterized by six important ideas: tracing 3D streamlines by use of the concept of ’time of flight?? (TOF) rather than arc length, expressing the mass-conservation equations in terms of TOF, periodic updating of the streamlines in time, solving the transport problems numerically along the streamlines rather than analytically, accounting for gravity effects, and extension to compressible flow. All of these improvements originated from the need to relax the limiting assumptions inherent in the early semianalytical streamtube methods and adapt the method to more-realistic and -complex reservoir scenarios (Batycky et al. 1997).
