A new residual-based variational multiscale (RBVMS) formulation for incompressible turbulent flows is proposed that is suitable for discretization using divergence-conforming B-splines. The proposed methodology results in a pointwise satisfaction of the zero-divergence constraint on the discrete velocity field. The velocity fine scales are residual-driven and constructed in a manner that is consistent with the divergence-free constraint on the discrete velocity solution. The resulting formulation is tested on laminar-and turbulent-flow benchmark problems showing excellent stability and accuracy characteristics in both regimes.

Summary In this paper, we present a geometric multigrid methodology for the solution of matrix systems associated with isogeometric compatible discretizations of the generalized Stokes and Oseen problems. The methodology provably yields a pointwise divergence‐free velocity field independent of the number of pre‐smoothing steps, postsmoothing steps, grid levels, or cycles in a V‐cycle implementation, provided that the initial velocity guess is also divergence free. The methodology relies upon Scwharz‐style smoothers in conjunction with specially defined overlapping subdomains that respect the underlying topological structure of the generalized Stokes and Oseen problems. Numerical results in both two‐ and three‐dimensions demonstrate the robustness of the methodology through the invariance of convergence rates with respect to grid resolution and flow parameters for the generalized Stokes problem and the generalized Oseen problem, provided that it is not advection dominated.

Highlights Women’s empowerment interventions are not as effective as hoped or intended. Could be an issue with intervention design and implementation. Research reveals that there are several limitations to existing women’s empowerment approaches. These include disregard of context, a non-holistic approach, difficulty measuring variables, etc. Vulnerability mapping may be able to address these limitations; we present an adapted framework.

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The first use of wired pipe in BP was in early pre-commercial field trials in seven Oklahoma wells in 2004to 2005(Reeves et al, 2006. IntelliServ commercialized its networked drillstring or wired pipe with full connectivity to 3 rd party downhole tools in early 2007.BP field trialed the commercial version of wired pipe with a comprehensive suite of BHI's Loging While Drilling (LWD) tools, Measurment while drilling (MWD) and AutoTrak rotary steerable on two Wamsutter (Wyoming) wells in 2007. These wells achieved a number of "industry firsts" including the first use of IntelliServ along string pressure measurements and the first use of real-time high resolution wellbore imaging while drilling.Since then, BP has deployed wired pipe commercially on more than 14 wells in 4 additional locations (Trinidad, North Sea, Colombia, and Deep Water Gulf of Mexico) representing a good cross section of drilling conditions and challenges (including wellbore stability, hole cleaning, BHA vibrations, formation pressure measurements in depleted zones, complex geology and challenging directional requirements). This paper is a summary of the above experiences. It includes a discussion of the challenges and solutions in area such as hardware modifications (e.g. wiring top drives, reamers, jars) deployment, logistics, reliability, pipe handling and other operational modifications, surface connectivity and dataflow to shore. The bulk of this paper discusses wired pipe enabled applications while drilling. Introduction:BP has been involved with IntelliServ since its early days (Jellison et al, 2003). Early field trials of wired pipe were conducted on BP wells in Oklahoma (Reeves et al, 2006). The objective of these trials was to test the mechanical and network reliability of the system. Attempts to use the real-time data were limited. In 2007, two wells in Wamsutter (Wyoming) were used for the "Wired Pipe enabled applications" field trial. The focus of these trials was to explore what the types of real-time applications that could be enabled by the additional data available while running wired pipe, or in others words "what can we do with wired pipe that we can't do with mud pulse". Although the Wamsutter wells themselves were not thought to be sufficiently challenging or high cost to warrant the use of wired pipe on a commercial basis, they did offer the opportunity to test a number of applications which were thought to be of significant use in other more challenging and higher cost locations (mostly offshore).

We examine a variational multiscale method in which the unresolved fine-scales are approximated element-wise using a discontinuous Galerkin method. We establish stability and convergence results for the methodology as applied to the scalar transport problem, and we prove that the method exhibits optimal convergence rates in the SUPG norm and is robust with respect to the Péclet number if the discontinuous subscale approximation space is sufficiently rich. We apply the method to isogeometric NURBS discretizations of steady and unsteady transport problems, and the corresponding numerical results demonstrate that the method is stable and accurate in the advective limit even when low-order discontinuous subscale approximations are employed.

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For many years the oil industry has been limited by the fact that measurements are only taken at the BHA and at surface during well construction operations. This has led to a reliance on modeling to help understand the measurements made and to understand the conditions in regions of the wellbore that are not being directly monitored. The advent of sensors that can be deployed along the drill string has created an opportunity, for the first time, for operators to observe the downhole environment not just at the BHA but throughout the entire wellbore. In order to realise the value of these measurements it is necessary to expand existing analysis techniques and develop new methods specifically designed to make use of this expanded sensor capability. BP was the first operator to commercially deploy the along-string measurement sensors in a development well (2008) and has been making use of the technology ever since. This paper presents some of the analysis methods used in these deployments as well as some of the lessons learned. It is shown that, while the addition of along-string sensors can increase the complexity of analysis, the information that can be gleaned from this data can be very valuable.