What is Monte Carlo Integration? Monte Carlo, is in fact, the name of the world-famous casino located in the eponymous district of the principality of Monaco on the world-famous French Riviera. It turns out that the casino inspired the minds of famous scientists to devise an intriguing mathematical technique for solving complex problems in statistics, numerical computing, and system simulation. One of the first and most famous uses of this technique was during the Manhattan Project when the chain-reaction dynamics in highly enriched uranium presented an unimaginably complex theoretical calculation to the scientists. Even the genius minds such as John Von Neumann, Stanislaw Ulam, and Nicholas Metropolis could not tackle it in the traditional way.

In recent years, Aker BP has explored and developed a number of digital improvements to optimize production. The underlying business drivers are meant to improve efficiency, increase production and reserves, decrease costs, and reduce the carbon footprint from operations. The example described in this article has innovative elements of digitalization and automation of workflows which provide a new approach for better handling of slugging in subsea developments with long tiebacks. The new solution has a potential for optimizing production and limiting the amount of flaring. Flow Instabilities in the Vilje Field The Aker BP-operated Vilje field in the Norwegian Continental Shelf has occasionally experienced production-flow instabilities in the production pipelines and risers due to slugging.

While commercial databases often provide summary information about basins that can be extracted easily with queries or even interactive tools, the explorationist needs to integrate such information with more up-to-date and in-depth descriptions of structural and sedimentary events occurring in the basin, descriptions that can be found only in unstructured documents. Key information about basins can be scattered across paragraphs, tables, and image captions of hundreds of technical articles, or can be embedded within pictures. Even when exploiting a traditional search engine with the name of the desired basin, the results can be unsatisfactory: first, not all the results might be relevant; second, many different variants of the basin name are often used within publications. In the optimistic hypothesis that the subset of relevant documents is found by the search engine, all key concepts related to a basin need to be understood by the geologist by careful examination of the paper text and images. Moreover, even if the published information (structured and unstructured) on a basin is found, there are different opinions expressed by different authors, in addition to the uncertainty of the data itself (such as the age of a formation or the details of the geological evolution of the basin), so that multiple conceptual models of the basin can be drawn from the uncertain and scarce information available. Some of these conceptual models are more probable while others are less probable, but sometimes the latter happen to be economically more valuable. Therefore, recovery of all relevant information about a basin is crucial, but also important is the preservation of differing opinions about the data—what might be termed minority reports. This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 197610, “Application of Geocognitive Technologies to Basin- and Petroleum-System Analyses,” by Paolo Ruffo, Marco Piantanida, SPE, and Floriana Bergero, Eni, et al., prepared for the 2019 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, 11–14 November. The paper has not been peer reviewed.

This article presents a new approach for engine room design based on the modularization concept including the part arrangement optimization. The characteristics of the proposed methods are as follows. First, attention was paid to piping systems of multiple bulk carrier series of different sizes. The cost and length of the piping system as well as the similarity and the commonness of the modules and arrangements were considered. Second, to define an effective module that could be commonly used in different ships, a design structure matrix was adopted. Third, in the arrangement design, an optimization system was developed using a genetic algorithm to obtain a similar pattern for module arrangement in multiple series ships with specific consideration toward cost and similarity. Some examples using the proposed method are shown at the end of article.

This paper presents the numerical analysis and optimization of the wave energy converter, Sea Wave Energy Extraction Device (SeaWEED), which is considered as an improved attenuator consisting of four modules connected by rigid truss structures. A potential-flow-based frequency-domain program based on the Lagrange multiplier method was developed to predict the hinged motions and the power takeoff (PTO) of SeaWEED. The numerical method was validated by using experimental data. Optimization studies were further carried out by considering various parameters, including damping coefficients of the PTO systems, lengths of truss structures, and draft of the device. The uniform design method was used for sampling, and the response surface method was employed for surrogate construction. An optimal combination of parameters was determined for an intended operation site.

Summary

Previous studies showed that different parameters influence the plugging of completion tools. These parameters include rock mineralogy, reservoir-fluid properties, and type of completion tools. Although different methods have been used for unplugging these tools, there is still debate regarding the performance of these methods on damage removal. In this study, we assessed the performance of high-power shock waves generated from an electrohydraulic-stimulation (EHS) tool on cleaning completion tools plugged during oil production. These devices were extracted from different wells in Canada, Europe, and the US. First, we quantified the extent of cleaning for the plugged slotted liners using the EHS tool at the laboratory scale. Next, we analyzed the mineral composition of the plugging materials removed after the treatment by conducting scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), inductively coupled plasma mass spectroscopy (ICP-MS), colorimetric, and dry-combustion analyses. Finally, we reviewed the pulsing-stimulation-treatment results applied to several field case studies. The results of unplugging slotted liners at the laboratory scale showed that up to 28.5% of the plugged slots are cleaned after 120 pulses of shock waves. The mineral-characterization results showed that the main plugging materials are calcite, silicates, and iron-based components (corrosion products). The cleaning performance (CP) of the EHS tool increases by increasing the number of pulses and the output energy (OE) applied to the tool. The CP parameter is high at (i) high concentrations of carbonates, barium (Ba)-based components, and organic matter, and (ii) low concentrations of corrosion products and sulfates. The results of field case studies showed that the cleaning of the EHS tool is not limited to the sand-control devices and it can clean other tools that are less accessible for other techniques, such as subsurface safety valves. This paper provides a better understanding of the performance of shock waves on damage removal from plugged completion tools. The results could open new insight into the applications of shock waves for cleaning the completion tools.

During the interactions between level ice and sloping offshore structures, crack initiations and propagations as well as the interactions between the resultant ice fragments occur. To simulate such complicated processes, the cohesive element method, which is capable of simulating dynamic fragmentation, becomes a potential numerical approach and has been applied to various kinds of offshore structures. One of the major challenges in applications of the cohesive element method is the mesh dependency or convergence issue for which remedies of random meshes and a random property field have been proposed in the context of concrete, ceramic, or glass fiber fracture problems. In this paper, random meshes based on Voronoi tessellations and a random ice property field following Weibull distributions were implemented into the numerical setup of the cohesive element method for level ice-sloping structure interactions to evaluate their performance in improving mesh convergence. Additionally, a new formulation based on added mass and hydrodynamic damping to capture the hydrodynamic effect of the fluid base was derived and utilized in the simulations. Based on a series of simulations, the time histories of the dynamic ice forces in the loading direction were compared with field data. It was found that an average Voronoi cell size close to the breaking length of the ice sheet yielded the best accuracy, since roughly all the cohesive interfaces near the structure failed in the simulations. This gives guidance in the determination of the average Voronoi cell size in the numerical setup according to empirical relationships between the breaking length and the ice thickness. Additionally, with the validated numerical model, the magnitude of the ice force in the transverse direction was found to be 30% of that in the loading direction, which serves as a preliminary method to determine the dynamic ice force in the transverse direction, facilitating the conceptual design of jacket structures with ice breaking cones.

The present article introduces a holistic approach to ship design, as it is being developed in the Horizon 2020 EU project HOLISHIP (www.holiship.eu). The project deals with the development of design and virtual prototyping simulation platforms, which integrate software tools for all major ship design disciplines and optimization objectives, namely, building and operational cost, energy efficiency, safety, environmental footprint, and life cycle cost/impact assessment. It enables the seamless mathematical multi-objective optimization of ship design with governing design constraints and the exploration of the huge design space by parametric modeling of the ship design system and its components. The article outlines the integration of the essential software tools into the software platform and demonstrates the functionality and benefits of the HOLISHIP approach by brief presentations of typical case studies.

Summary

This study discusses the development of a finite element analysis (FEA) model that describes the bending and straightening process of coiled tubing (CT) at the wellhead and the buckling process after CT is run in wells. On this basis, this study calculates the initial residual bending configuration quantitatively for the first time and describes the residual stress and strain-changing regularity. The initial residual bending configuration of CT under wellbore constraints after running into the hole is sinusoidal, which essentially affects the CT downhole mechanical behavior. Simulating the buckling process of the CT string in the vertical and horizontal sections with the CT string assumed straight served as control subjects. This study verifies the accuracy of the numerical simulation method by comparing the results of critical buckling loads to previous research results. The initial residual bending configuration significantly affects axial load transfer and reduces the least axial force required to produce a helical buckling in the wellbore. The residual stress induced by the bending and straightening process at the wellhead makes the buckling and buckling release of CT downhole an elastic-plastic process, whereas it becomes an elastic buckling process if the initial configuration of the CT string is assumed straight. The comparison between the buckling process of CT with residual bending and CT without residual bending shows that the effect of residual bending on CT cannot be ignored when studying the downhole mechanical behavior or job design.

Summary

Linear network models are promisingly simple progressive cavity pump design tools. Current linear network models are difficult to use in the design process because they require calibration against experimental data or computationally intensive simulation. In this paper we present new approaches for implementing linear network progressive cavity pump models and provide new methods to accurately and quickly estimate the values of each resistor in the model from pump geometry for both laminar and turbulent flows. This paper also argues that sealing-line flow transitions from laminar to turbulent at orders of magnitude smaller Reynolds numbers than described in the literature thus far. We propose a new hypothesis for the point of transition to turbulent performance.