High Performance Software's Simulation Workflows Improve Decision-Making Efficiency for Asset Engineers and Managers

To make sound E&P investment decisions, asset teams require a decision management system that optimizes decision-making in complex field development environments and economic conditions in order to manage associated risks in an industry atmosphere of increasingly compressed timeframes. Therefore, it is vital that operators understand how the total asset is expected to perform so an environment for making optimal field development decisions can be created.

Nexus® Software Optimized for the DecisionSpace® Environment
Landmark's Nexus® software provides integrated reservoir simulation workflows that generate results faster than any other commercial simulation solution. It is a single simulator with a generalized compositional approach. With the exception of PVT calculations, the simulator executes the same code whether the fluid is black oil or compositional. The only input changes required are those for fluid data.

Designed expressly to serve asset teams, Nexus software enables users to quickly make robust production and reserve forecasts, improve field development and facilities planning and optimize the value of the total asset. It also allows multiple reservoirs of varying fluids and formulations to be coupled seamlessly, tied to a common surface facility and solved as one fully coupled simulation solution.

To provide more stable and accurate full-field modeling, Nexus software solves the surface network equations simultaneously with the sub-surface equations. In each iteration, the surface nodes and subsurface grid cells are solved simultaneously. This is unique in the industry and results in a truly accurate representation of the total surface-subsurface asset.

Nexus software offers dramatic reductions in run-time for full field reservoir simulation of single or multiple reservoirs tied to a common surface network compared to the traditional offering of reservoir simulators (Click image to enlarge).

The Network Planner module enables fast and automated generation of surface plans including features such as flow lines, valves, chokes, manifolds, gas plants, and separators. The network is saved in the Nexus format and simulated by Nexus software tightly coupled with the subsurface, resulting in a better understanding of reservoir behavior.

A unique volume balance formulation in the Nexus software achieves simulation acceleration of up to 20 times faster compared to leading industry simulators, and the simulator conserves the component mass and can simulate multiple reservoirs allowing different physics and formulations to be coupled seamlessly. Multiple reservoirs tied to common surface network are solved rapidly as one single simulation system. Thus, full-field simulations can be accomplished in hours instead of days.

Clients Benefit from Nexus Software
Asset teams realize more accurate production forecasts from the simultaneous surface and subsurface simulation that employs a fully coupled, fully implicit formulation. Also, the direct access modeling environment improves user productivity by eliminating the need for data transfers and data reformatting. Data preparation and analysis is fast and easy using the intuitive windows-based SimDataStudio™ pre- and post-processing module.

Nexus Software at Work
Case History No. 1
The Operator Challenge:
An operator managing a deepwater offshore asset in Africa comprised of several reservoirs was using a reservoir simulation solution that was performing poorly. The size and simulation run-times necessitated that two of the models use grid coarsening and, even with the resulting reduced grid size, performance remained poor. When coupling multiple reservoirs together, run-time performance was limited by the worst performing individual model. Modeling was very slow, and did not allow for multiple iterations.

The Halliburton Solution:
Because the operator needed a fast, multiple reservoir simulator that could handle both surface and sub-surface simulations simultaneously, Halliburton proposed that DecisionSpace® Nexus software be employed on this challenge as a solution pilot project. The operator agreed to the proposal and existing reservoir models were converted to use Nexus software simulation technology.

A coupled Nexus model was created by connecting the individual models. The operator's FPSO gathering system was modeled using hydraulic tables, and each reservoir was connected to the gathering system by creating connections to the appropriate sea floor nodes. As individual models were updated, the coupled system was also updated dynamically. The coupled system could be run in either serial or parallel mode.

When run in parallel mode, reservoirs can be broken into pieces for increased efficiency. This allows more detailed models to be run without unduly impacting simulation time.

The Client Value Realized
Almost immediately, the two coarsened reservoir models showed an improvement of 6X - 20X over the existing models, with the simpler models showing a speed improvement of up to 3X - 5X faster. Following other significant improvements in simulating the reservoirs for asset optimization, the client told Halliburton that they considered the pilot project a success. The client is continuing to use Nexus software technology.

Case History No. 2
The Operator Challenge:
A Middle East operator required reservoir simulation technology to solve pressing technical and business challenges associated with modeling reservoirs and surface facilities.

The Halliburton Solution:
Halliburton's DecisionSpace Nexus software technology was utilized to simulate four reservoirs tied to a common surface facility. Originally, the operator was required to use multiple simulators to simulate each of the four reservoirs. The existing workflow consisted of managing the production data for each reservoir in a spreadsheet and then correlating that with the productivity of the surface facility.

The Client Value Realized
The Nexus software enabled the operator to analyze all four reservoirs simultaneously and then couple them to the surface facility and simulate them as one system very quickly which allowed the operator to make the required technical and business decisions required in managing this asset.

Summary
The Nexus software solution is being actively implemented worldwide on various assets with varying fluids and complexities. It offers asset managers and engineers tremendous opportunities for reducing operating costs and making large capital expenditure decisions more efficiently than ever before. Nexus software can solve the surface network simultaneously with the sub-surface equations to provide more accurate full-field modeling and the unique volume balance formulation in the technology achieves simulation acceleration of up to 20X faster when compared to leading industry simulators.

A major advance in reservoir simulation, Nexus® software enables fully implicit, fully coupled surface-to-subsurface simulation for a comprehensive look at your asset (Click image to enlarge).