LR Senergy’s new process uses computational fluid dynamics (CFD) to model a well and near wellbore — and subsequently identify production optimization options and strategies. Jeannie Stell reports.
Michael Byrne. Images from LR Senergy.
Wellscope is a new innovative process, developed by Aberdeen-headquartered LR Senergy, which can be used to model an entire well and subsequently identify production optimization options. The process was co-invented by Michael Byrne, global technical head of formation damage for LR Senergy.
Byrne, with a background in formation damage, joined the firm about eight years ago, and began working with a team that was striving to find an efficient method of modeling near-wellbore inflow. The team wanted to capture data on how oil and gas flow from the reservoir into the well, particularly into the near-wellbore, which is an area very close to the well but is still actually in the reservoir.
“This area is of particular interest because that is where formation damage occurs,” Byrne says. “We identified that this modeling process, called computational fluid dynamics (CFD), might be the key to improving the way that we model the near-well bore fluid flow, which would help us to better understand how wells are performing and how much better they could perform.”
As part of a lower completion erosion risk assessment, Wellscope can be used to build complex completion geometry, in this case including the reservoir, perforations and sand control screen. The screen shroud and the base pipe are included as their configuration can have a significant impact on the velocity and thus erosion risk of the sand control screens.
Byrne and his team began to apply CFD and found that it was a very appropriate technology that had never been used before in the exploration and production industry to model near-wellbore flows to the accuracy that LR Senergy hoped to achieve.
The company began with the objective of improving the process of modeling formation damage in near-wellbore sections. As the team continued to work with the evolving technology, it began to illustrate that the process and technology could be used to model flow from very deep in the reservoir, then into the well and through the well.
“This process does not yet follow the flow right to the surface, but I think that will come one day,” Byrne says. “But so far, we have managed to use this CFD, which is used in many other industries, and indeed in our own industry at the surface, and we have taken this down into the wellbore.”
Byrne and his team are applying this process to understand how various types of wells can perform, how various types of completions will perform, and what the impact of formation damage and flow restrictions will be. “Because this is a modeling process that deals very efficiently with fluid flow through restrictions, it is the most appropriate technology that we can find to model near-wellbore inflow and in-well flow,” he says. LR Senergy has continued to expand the various applications that can benefit from the technology.
The Wellscope process was difficult to patent because the technology is neither equipment nor software, which are typically where patents are granted. “We wanted to patent the process of using this CFD technology to model fluid flow in the near-wellbore,” Byrne says. “The difficulty for patent examiners was to compare this with many other patents and determine if there had been any prior usage and see if it truly is innovative.”
Also, the examiners were inclined to associate CFD with computers and software, due to the word “computational,” and this created a challenge because software cannot be patented in the UK, Byrne explains. “It took some convincing to help the examiners understand that this is indeed an innovative process and it is the first application of this particular modeling technology in the sector in which we are applying it.”
Fortunately, the firm successfully secured the two patents — one in the US and one in the UK — six years after making the initial applications. The patents protect the LR Senergy process under the product name Wellscope that uses CFD to model pore spaces in the ‘skin’ zone of a well or a full well, after which various completion scenarios can be produced to identify the best options for significant optimization of wellbore designs and production.
The US patent, US8849637, is for the process for modeling production from a subterranean region. The original UK patent, GB2474275, protects well simulation or the process of optimizing the design of a wellbore. A subsequent UK divisional patent, GB2515411, broadens the scope of the patent coverage to include other topics such as simulation of well testing, development of software, and more.
Offshore, Wellscope was used in an application West of Shetland to assess the impact of formation damage based on return permeability. The model showed that well flow-back in injectors had a negligible impact on injectivity. The predictions ultimately resulted in a cost saving of more than US$5 million per well.
Elsewhere, Wellscope was used by Talisman to understand the flow dynamics and production potential of some Gyda field wells, in the southern Norwegian section of North Sea. Talisman used the results to make completion choices.
“Standard modeling techniques could not model our proposed complex recompletion,” says Barry Goodin, senior exploration engineer for Vermillion Oil & Gas. “The Wellscope process helped us evaluate both the optimum perforation strategy and the viability of a challenging and expensive workover recompletion. Detailed numerical two-phase fluid modeling of the well inflow helped us understand and predict the performance of the well.”
To date, Wellscope has been used in more than 30 projects in the UK, Western and Eastern Europe, the Middle East, Scandinavia and Asia.