Day 2 Tue, August 17, 2021最新文献

{"title":"Taylor Bubbles of Viscous Slug Flow in Inclined Pipes","authors":"L. Dafyak, B. Hewakandamby, Ahad Fayyaz, D. Hann","doi":"10.4043/31238-ms","DOIUrl":"https://doi.org/10.4043/31238-ms","url":null,"abstract":"\u0000 Unique structures are formed when gases and liquids flow simultaneously in pipelines. The geometric characteristics of these structures are fundamental parameters in intermittent flow regimes. The length of liquid slugs and Taylor bubbles are inputs to mechanistic and empirical models for pressure drop estimation, slug catcher sizing and determination of the periods of no or low liquid in pipelines. Although slug flow has been studied for decades, there still exists a lack of comprehensive understanding of flow structures dynamics due to the complex interactions between the gas and liquid phases in two-phase flow. This study investigates the influence of pipe inclination on the length and hydrodynamics of large gas structures in intermittent flows, particularly, ‘Taylor bubbles’ in slug flow regime. An experimental study was conducted in a 67 mm ID pipe to estimate the bubble lengths of an air-silicone oil mixture from void fraction measurement using a twin-plane Electrical Capacitance Tomography (ECT) tool. The results show that the pipe inclination, gas and liquid flow rates have a substantial effect on the length of large bubbles in slug flow. Taylor bubbles get longer when the void fraction increases, or the pipe inclination deviates towards the horizontal pipe orientation. The influence of pipe inclination on bubble length is quite significant; this variation in bubble length with pipe inclination is attributed to the expansion or compression of large gas structures when there is an alteration on the forces acting on the bubble nose. The weight of the liquid column above the bubble nose which has been often neglected in earlier models was identified to have a notable effect on the volume occupied by the large bubbles and consequently, its length. A semi-mechanistic model is proposed based on the analysis of forces acting on the Taylor bubble nose in a quiescence liquid phase. A comparative analysis of the model and previous models shows that the proposed model outperforms existing mechanistic and empirical models across all pipe inclinations. This study gives an insight into the effect of pipe inclination on the length of large bubbles during slugging in pipes, as these bubbles can be up to 10 times longer in horizontal pipes compared to vertical pipes at the same flow conditions. The proposed model has the potential of estimating the length of large bubbles across all pipe inclinations in upward slug flow with acceptable accuracy, particularly for pipelines installed in undulating terrains.","PeriodicalId":10936,"journal":{"name":"Day 2 Tue, August 17, 2021","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84922045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mapping Complex Geological Surface Morphology During Landing Operations Using 3-D Inversion of Ultra-Deep Electromagnetic LWD Data","authors":"N. Clegg, Ana B. Domingues, Rosamary Ameneiro Paredes, Nicki Gardner, V. M. Barrón, Eliot Rowden, Dave Marchant","doi":"10.4043/31216-ms","DOIUrl":"https://doi.org/10.4043/31216-ms","url":null,"abstract":"\u0000 Ultra-deep azimuthal electromagnetic (EM) logging-while-drilling (LWD) tools are frequently used during landing operations for early detection of the reservoir top. This enables alterations to the well plan before the reservoir is penetrated. To date, this approach has relied on one-dimensional (1-D) inversions that accounts only for changes in resistivity above or below the wellbore. When geology is complex, resulting in lateral changes in resistivity, 3-D inversion of EM data is required to provide increased reservoir understanding.\u0000 This paper presents a case study from offshore Brazil, targeting a turbidite deposit. A complex reservoir surface was expected, as defined by seismic data for the area. Although top structure rugosity and lateral position uncertainty had been incorporated into the prognosis, the impact of surface topography on inversion results while landing was not anticipated. During real-time operations, 1-D EM inversion was used along with correlation of shallow LWD data to map the reservoir top. It was clear the geology was more complicated than depicted by the 2-D geological model constructed from the 1-D inversion and that lateral changes in surface morphology may be occurring. Post well a 3-D inversion of the EM data revealed the 3-D geological structure.\u0000 During the initial approach, the 1-D inversion indicated that relief of the reservoir top was more exaggerated than expected; the well intersected a sharp peak prior to approaching the target zone. The misfit on the 1-D inversion indicated there was potential for lateral variation in resistivity, influencing the 1-D results; lateral changes can produce artefacts that obscure the subsurface structure. This was confirmed after drilling with analysis of ultra-deep azimuthal resistivity images, indicating significant changes in resistivity to the left and right of the borehole. A 3-D EM inversion was run to depict these complex subsurface geometries. The 1-D inversion results were better understood post-drill with the 3-D inversion results, which show a high point in the reservoir top to the side of the wellbore that was drilled past, but not penetrated by, the well. This high-resistivity zone had a negative effect on the 1-D inversion results and made delineation of the reservoir top difficult.\u0000 Understanding lateral variations in formation and fluid boundaries can improve well placement and reservoir understanding. This knowledge can impact landing scenarios and well placement within the reservoir. Three-dimensional inversion of ultra-deep azimuthal EM LWD data in real time will provide a clearer picture of the position of resistivity changes while drilling. This will enable decisions to be made that affect the azimuthal position of a well, as well as its vertical position during drilling, thereby facilitating optimal well placement, even in complex geological environments or for infill wells requiring precise well placement.","PeriodicalId":10936,"journal":{"name":"Day 2 Tue, August 17, 2021","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86153870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accelerated First Oil With Integrated Execution Model, Digital FEED Platform And Product Standardization","authors":"Hemant Priyadarshi, Chris Waskow, C. Cruz, J. Sammon, T. Parenteau","doi":"10.4043/30924-ms","DOIUrl":"https://doi.org/10.4043/30924-ms","url":null,"abstract":"\u0000 This paper illustrates how a subsea integrated (\"SURF – Subsea Umbilicals Risers Flowlines\" and \"SPS – Subsea Production systems\") execution model can be significantly improved in further reducing the time to first oil. It illustrates the use of digital platforms for FEEDs (Front End Engineering and Design) and Configure to Order (CTO) product designs to provide further schedule improvements resulting in an enhanced execution model. The time to first oil is considerably improved by cruising through the Front-End design gates using digital FEED platforms. CTO designs enable a project to reach the manufacturing gate faster by reducing detailed engineering effort significantly and in some cases eliminating it. The paper provides an introduction to the conventional execution model (Split SURF and SPS scopes), the integrated execution model (combined SURF and SPS scopes) and the enhanced integrated execution model (using digital FEED platform and CTO products). A comparison has been made on project delivery schedules between the three models illustrating the schedule savings through use of digital FEED platforms and CTO designs. It concludes that digitalization of FEEDs and standardization of product configurations create value for the operators in context of faster return on investment. Digital FEEDs are a new concept and still in its infancy. CTO design is a known concept; however, in context of a subsea project, how it may improve schedule delivery is not well established. These factors are truly an enhancement to the integrated execution approach and the additional value gets delivered to the end customer by further accelerating the time to first oil.","PeriodicalId":10936,"journal":{"name":"Day 2 Tue, August 17, 2021","volume":"26 6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83831942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How Brazil Operators and Regulators Implemented, Audited and Learned from COVID-19","authors":"Nate Biddle, J. Siqueira, A. Guedes, Mariana R França, Nayara Ferreira, Daniela Coelho","doi":"10.4043/31255-ms","DOIUrl":"https://doi.org/10.4043/31255-ms","url":null,"abstract":"\u0000 The COVID-19 pandemic brought with it the potential risk for personnel abandonment of various oil and gas installations that was unprecedented in the industry. Uncertainties on how to implement and monitor these processes was a significant challenge. This pandemic scenario required that operators and regulators work together to reformulate their normal way of working to decrease the risk of virus exposure to personnel, while still ensuring critical elements were implemented for safe operations.\u0000 Regulators were required to act quickly to implement and adjust regulations to meet the new demands for safe operations during the global pandemic. Through joint discussions with industry associations and an understanding of the situation, the Brazilian oil and gas industry regulator, ANP, was able to immediately implement tracking requirements and, within less than one month after formal declaration of a state of emergency, issued new regulations for the restart and operations of installations. These measures assisted in a better understanding of the COVID-19 situation onboard offshore installations and in disseminating learnings across Exploration and Production (E&P) industry.\u0000 Operators across Brazil all implemented modified emergency response plans, new hazard identification measures and means to reduce the risks of these identified hazards in response to COVID-19. The ANP worked to oversee the manner in which these measures were conducted, while successfully assisting in reducing demands on offshore work during the pandemic by migrating to a fully-remote means of regulatory enforcement and auditing.\u0000 Regulators and operators all worked across five key areas and within the joint efforts significantly mitigated the impacts which COVID-19 had on the industry in Brazil. These key areas were:\u0000 Operational Safety Documentation, procedures within the regulations and management system to cope with the pandemic scenario; Tracking of COVID-19 cases and effective response measures/learnings across industry; Hazard Identification related to the operational conditions impacted by the COVID-19 crisis; Risk Assessment for the identified hazards because of the pandemic; and Emergency Response plans for response to the worst-case operational scenario during a pandemic.\u0000 Although severe outbreaks did occur on several installations, causing temporary shutdowns, there have to date been no major operational accidents as a result of COVID-19 personnel evacuations or procedures. Additionally, the total oil and gas production levels for Brazil have been maintained or increased across the sector. These high-level performance indicators demonstrate that through the efforts of the ANP, operators, service providers and other regulators, the pandemic situation is being managed successfully while the industry also continues meet the necessary energy demands of the country. Although the global pandemic has been a sobering and dark period in history for all, there have been posi","PeriodicalId":10936,"journal":{"name":"Day 2 Tue, August 17, 2021","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90772196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}