SAGD reservoir simulation gets a boost from virtual and augmented reality at the University of Calgary

Image: U of C

A team of researchers at the University of Calgary (U of C) is using virtual reality (VR), augmented reality and advanced visualization techniques to help SAGD producers better manage their complex reservoirs to optimize operations and improve costs.

Their tools are even being used to help one SAGD operator bring back online wells that were temporarily shut in during the wildfires this spring.

The group is led by Zhangxing (John) Chen, NSERC/AITF/Foundation CMG industrial research chair in reservoir simulation at the U of C’s Schulich School of Engineering.

According to Chen, VR is great for scientific visualization because of the larger variety of interaction possibilities compared to a traditional desktop, as well as the complete immersion and preservation of spatial perception.

For example, research has shown that a specific benefit of VR is that it allows spatial judgments that require careful visual inspection of small objects, he adds.

Another benefit is the ability to work with and analyze 3-D data in 3-D, which is more straightforward and intuitive.

Also, he says there has recently been a lot of investigation into improving the analysis prior to simulation using heuristics, exploratory analysis and proxies, to ensure that valuable time spent in simulation is more targeted and provides greater value to a project.

“These techniques benefit from collaborative interactive methods such as the ones we use in our large-scale VR system,” says Chen.

Visualization techniques and hardware in general are advancing rapidly. A lot more is possible on desktops and even tablets and phones than was ever possible in the past.

“This is even more the case for other mediums such as virtual reality and augmented reality,” he says. “Although the promise of the technology was appreciated a decade ago and even earlier, only now has the hardware, the tools and the maturity of interaction design caught up to the promise.”

The collaboration centre is used to visualize data for internal and external collaboration, teaching, presentations and outreach.

Commercial tools run existing desktop applications in VR applications to show data sets; however, there are limitations to these tools since they are translating 2-D applications to a 3-D medium but are not actually 3-D applications.

For this reason, and to support specific directions, the University of Calgary team has developed its own applications. “Although our applications are prototypes, we have had positive feedback and hope that as they become more mature they will be used to support our projects,” says Chen.

The team also has an advanced visualization facility where members use 2-D and 3-D technology to analyze complex data sets to collaborate and demonstrate projects.

“By having a facility that can support a variety of visualization mediums, we have maximum flexibility to match the correct visualization need with the appropriate technology,” Chen says.

Having this flexibility allows the engineers to research innovative approaches that can help analyze complex scenarios.

“For example, we are developing tools that can take advantage of [VR] in a variety of platforms including commodity head-mounted displays or large-scale collaborative VR in our advanced visualization facility.”

Heat-loss modelling

One key issue that needs to be addressed is the need for better heat-loss modelling. The U of C team has developed a standalone thermal wellbore simulator to handle several different wellbore configurations and completions. It can also be fully coupled with the facility’s SAGD simulator.

The simulator uses a fully implicit method to model heat loss from tubing walls to the surrounding formation, says Chen.

Instead of implementing the common Ramey method—which has been around since 1962 for heat-loss calculations and has been shown to be a source of large errors—Chen’s team’s wellbore simulator runs a series of computational fluid dynamical (CFD) models for the buoyancy-driven flow for different annulus sizes and lengths and a number of tubings.

Based on these CFD models, correlations are derived that can conveniently be used for more accurate heat-loss estimation from the wellbore to the surrounding formation for SAGD injection wells with single or multiple tubing strings, he explains.

The wellbore simulator can handle thermal processes that involve sophisticated wellbore configurations, complex fluid flow and heat transfer in the tubing, annulus, wellbore completion and surrounding formation.

It can also look at complex but common wellbore configurations such as multi-parallel or multi-concentric tubings, says Chen.

ConocoPhillips Canada and Brion Energy get the first crack

The wellbore simulator is being used by industrial sponsors Brion Energy and ConocoPhillips Canada.

ConocoPhillips is testing the technology to potentially solve challenges it has with hot spots (steam from a SAGD injector bypassing directly to a producer) and to help it bring on wells that were shut in for a month due to the Fort McMurray wildfires in May.

The U of C’s standalone thermal wellbore simulator provides real-time information and connects directly to the reservoir, says ConocoPhillips Canada reservoir engineer Chao (Charlie) Dong,

“It’s good to have a simulator to give you real-time situation on the ground without spending too much money on measurement,” Dong says. “We’re still testing the software. It’s quite beta, but we’ve had some successful applications.”

Optimization run times drop significantly

In another reservoir modelling improvement, the university’s reservoir simulation group has developed a parallelization technology for running a SAGD simulator on multiple cores or central processing units (CPU) on a cluster.

The parallel SAGD simulator can be run on thousands of CPUs simultaneously in a parallel fashion, and it can potentially be thousands of times faster than a serial SAGD simulator on a single CPU.

“This means that a simulation run that used to take days or even weeks to complete now requires only several minutes.”