Day 4 Thu, May 09, 2019最新文献

{"title":"Scouring and Mitigating Efforts for the M3 Wave APEX Device","authors":"Mike Morrow, Ajay Shastri, M. Delos-Reyes","doi":"10.4043/29298-MS","DOIUrl":"https://doi.org/10.4043/29298-MS","url":null,"abstract":"\u0000 Submerged Pressure Differential wave energy converters have the potential to avoid many of the challenges facing surface floating devices, but they have their own unique challenges. Although sediment scour has historically been studied around simple columns and piling structures, scour around unusual structural geometries on the bottom of the ocean in the near shore environment is not as well understood. This paper provides a review of recent work to develop and validate numerical modeling methods that can predict scour around complex submerged structures as well as potential countermeasures to mitigate the impact of wave-induced scour.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123126914","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":"Research on Ocean Wave Spectrum and Parameter Statistics in the Northern South China Sea","authors":"Botao Xie, Xuhe Ren, Xu Jia, Zhigang Li","doi":"10.4043/29547-MS","DOIUrl":"https://doi.org/10.4043/29547-MS","url":null,"abstract":"\u0000 Environmental processes are random in nature and represent a necessary input for evaluation of environmental loads. Accurate estimates of wave parameters are becoming increasingly important for the floating platform design in South China Sea (SCS). This paper is organized as follows. To begin with, we provided a brief introduction on the measuring instrument and field data. Then, seven types of ocean wave spectrum models were compared by with the observed data. The result of calculation showed that the JONSWAP spectrum had a good precision and a wide suitability under various sea states in SCS. Next, the peak enhancement factors of JONSWAP were calculated. In order to evaluate the evolution of peak enhancement factor under typhoon condition, the observed data at different water depths were analyzed. Subsequently, the non-dimensional wave spectrums spectra under the specific wind grade were proposed and the results can provide reference for offshore operations. The ratios between maximum wave height (Hmax) and significant wave height (Hs) were determined finally. The research results about for the characteristics of a wave had been used in the engineering design for several projects in China.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117009223","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":"Extreme Sub-surface Currents Observed in the Northern Brazil - Suriname Region","authors":"R. V. Schiller, Rosemary B. Smith","doi":"10.4043/29426-MS","DOIUrl":"https://doi.org/10.4043/29426-MS","url":null,"abstract":"\u0000 Offshore waters from Northern Brazil to Suriname are subject to extreme curents driven by the North Brazil Current (NBC) and NBC Rings which represent a significant metocean hazard for the O&G Industry. Although extreme surface currents are well known, there is still a gap in the understanding of extreme sub-surface currents in that region. The objective of this paper is to further elucidate the characteristics of significant sub-surface currents and provide metocean guidance to the O&G Industry based on three separate long-term mooring campaigns in the region. Our investigation demonstrates that extreme sub-surface current events exist offshore Northern Brazil, French Guyana and Suriname. The events were mainly characterized by northwestward peak currents from 0.82m/s to 1.22m/s within 150m-300m below the surface. They were more frequent offshore Northern Brazil and French Guyana where events were observed within 2-3 months of each other. Offshore Suriname, only one event was reported in 14 months. Sub-surface current events took place during times when the surface circulation was relatively weak and during times when surface currents were strong and affected by the NBC / NBC Ring circulation. Offshore Northern Brazil and French Guyana, it is suggested that significant sub-surface currents could take place around the time when a NBC Ring is sheeding and the surface circulation is unstable. Extreme sub-surface currents could be decoupled from the surface circulation and that poses an additional challenge in terms of predicting when extreme sub-surface currents could take place. The findings of our study provide a new regional picture of extreme sub-surface currents from Northern Brazil to Suriname and highlight that those events must be accounted for by offshore O&G developments in that region.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130478699","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":"Performance Characteristics of the NoiseSpotter: An Acoustic Monitoring and Localization System","authors":"K. Raghukumar, G. Chang, F. Spada, Craig Jones","doi":"10.4043/29425-MS","DOIUrl":"https://doi.org/10.4043/29425-MS","url":null,"abstract":"\u0000 In support of monitoring technologies to evaluate the potential environmental effects of offshore energy devices, this project attempts to ultimately improve upon traditional acoustic sensing techniques by developing a cost-effective compact array of acoustic vector sensors that characterizes, classifies, and provides accurate location information for anthropogenic and natural sounds. The NoiseSpotter consists of three acoustic vector sensors arranged in a three-dimensional array deployed as a seafloor mooring. Each vector sensor measures acoustic pressure and the three-dimensional particle velocity vector associated with the propagation of an acoustic wave, thereby inherently providing bearing information to an underwater source of sound. Here, performance characteristics of the NoiseSpotter are presented, along with an analysis of its abilities as an operational passive acoustic monitoring system to characterize sources of sound. Data are presented from controlled acoustic transmissions in a quiet environment and an energetic tidal channel in the presence of non-acoustic flow noise. NoiseSpotter performance is demonstrated through its modular design, ease of deployment/recovery, ability to remove signal contamination by flow noise and the ability to geolocate acoustic sources of interest.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"180 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116314371","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":"Monitoring Stored CO2 to Document Permanence","authors":"S. Hovorka","doi":"10.4043/29525-ms","DOIUrl":"https://doi.org/10.4043/29525-ms","url":null,"abstract":"\u0000 Injection of CO2 into porous rocks deep in the subsurface intrinsically has a low risk of leakage for three reasons: (1) Although CO2 is buoyant compared to brine, layered rocks limit vertical migration. Injection zones are chosen with at least one well-qualified confining system that should isolate CO2 within the selected interval. (2) Capillary trapping of CO2 in the pore system, dissolution of CO2 into formation fluids, and sorption and reaction of CO2 with organics and minerals will further attenuate CO2 lateral or vertical migration. (3) Wells are designed to isolate fluids in the deep subsurface from the overlying water and other resources; even a poorly constructed well will greatly retard migration of stored CO2.\u0000 To add certainty to the planned storage, a monitoring program can be designed to document that the plume is migrating as predicted (and therefore that the planned-storage permanence is likely) and to assess any remaining uncertainties, for example, to further reduce well leakage or off-site migration risk.\u0000 In an offshore setting, time-lapse seismic is the most preferred tool. A survey collected prior to injection provides the baseline survey. Injected CO2 displaces water and also increases pressure. During repeat surveys, the resulting changes in seismic velocity are measurable. Subtracting the repeat surveys from the pre-injection survey provides a high-quality image of the areas where CO2 has migrated.\u0000 Other tools of high value are downhole-pressure measurements and wireline logs used to assess the zones at which CO2 is leaving the injection well(s). Gravity surveys are also used to assess the change in fluid density as CO2 is emplaced, and seismic sensors may be of value to assess microseismic response to injection. An available suite of environmental tools can be deployed to determine if any unexpected change occurs in the overburden, sediment, and water column. Advanced deployments such as fiberoptic cables and remotely operated sensor packages may have high value.\u0000 Complexities of and limitations to monitoring must be critically assessed. The material impact of loss of CO2 from storage is forward modeled to determine if tools and techniques selected are sensitive to the changes. For example, if natural gas charge is present in the subsurface, seismic change from injection of CO2 is likely to be small and may be less than noise. Only by rigorous documentation that leakage is detectable can the expected outcome, high-quality storage, be documented. New work is being undertaken to develop optimized and commercializable monitoring for storage projects in the Gulf of Mexico.\u0000 This work is related to a new multiyear project assessing the suitability of nearshore Gulf of Mexico for CO2 storage.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115311286","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":"Recalibration of Axial Pile Capacity Methods","authors":"B. V. Dijk, K. Kaltekis","doi":"10.4043/29406-MS","DOIUrl":"https://doi.org/10.4043/29406-MS","url":null,"abstract":"\u0000 The Lehane et al. (2017) pile load test (PLT) database (new PLT database) is one of the results of a joint industry project (JIP) to investigate the reliability of (CPT based) axial pile capacity methods for driven piles. The database contains results of high quality axial load tests of piles in sand and clay. This database was used to recalibrate five pile design methods for axial pile capacity of offshore piles. The methods considered were:\u0000 For sand:\u0000 Fugro-05 (Kolk et al., 2005)\u0000 Fugro-05 (ISO, 2016)\u0000  \u0000 For clay:\u0000 Kolk and van der Velde (1996)\u0000 Centre for Civil Engineering Research and Codes (CUR, 2001)\u0000 Van Dijk and Kolk (2010)\u0000 The recalibrated methods obtain a lower coefficient of variation (COV) and a better prediction of the mean of the measured capacity of the PLTs of the new PLT database and hence they can be considered more reliable than the original methods.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115137606","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":"Developing Probabilistic Risk Assessment, PRA, for a BOP System Reliability","authors":"J. Holmes, Viral Shah","doi":"10.4043/29544-MS","DOIUrl":"https://doi.org/10.4043/29544-MS","url":null,"abstract":"\u0000 Recent regulatory changes have moved in the direction of more oversight and more prescriptive solutions. One of the areas that can help operators and drillers alike deal with the new regulations is improved risk analysis. This paper addresses a methodology for Probabilistic Risk Analysis (PRA) modeling of blowout preventer (BOP) systems. The PRA utilizes a combination of event trees and fault trees to determine the probability of a hazard under a given set of conditions. The fault trees are populated with reliability data from the best available sources.\u0000 Traditional BOP risk analysis was done on a deterministic approach. The probabilistic approach will allow a logical method to assess top level hazards resulting from specific component failures. This approach has been used in other industries such as nuclear power and space exploration. A method of combining testing intervals with PRA results to determine the probability of failure on demand is also included.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126242411","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":"Simulation Study Comparing Offshore Versus Onshore CO2 Well Blowouts","authors":"C. Oldenburg, L. Pan","doi":"10.4043/29461-MS","DOIUrl":"https://doi.org/10.4043/29461-MS","url":null,"abstract":"\u0000 We have simulated onshore and offshore blowouts of an idealized CO2 injection well using T2Well, a state-of-the-art coupled well-reservoir simulator. The purpose of the study is to understand dynamic multi-phase non-isothermal flow phenomena in CO2 wells to inform risk assessment studies for offshore geologic carbon sequestration sites. The scenario we chose consists of a vertical well of 3050 m length completed in a mature geologic carbon sequestration reservoir filled with CO2 connected to a horizontal surface pipe. At time zero, we assume the surface pipe was breached producing a 2-inch diameter hole. In the onshore scenario, the pipe blowout causes CO2 to enter the ambient air at 0.101325 MPa and 22.78 °C, whereas in the offshore scenario the blowout is into the water column at a depth of 50 m where pressure and temperature are 0.598 MPa and 22.78 °C, respectively. The simulations show that the overall CO2 leakage rates are very similar for the onshore and offshore scenarios, with subtle differences in flow rates of various phases likely arising from differences in pressure at the leakage point. Overall, the main differences between onshore and offshore CO2 blowouts are expected to arise mostly after discharge due to differences between how CO2 disperses in ambient air versus in the water column.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132696976","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":"Next-Generation Hybrid Drill Bit Produces Exceptional Drilling Dynamics and Time-Saving Improvements","authors":"K. Bone, B. Bradley, Ibrahim Kale","doi":"10.4043/29440-MS","DOIUrl":"https://doi.org/10.4043/29440-MS","url":null,"abstract":"\u0000 An offshore field has presented a challenging intermediate drilling application. The 2200-m section was drilled in a 17.5-in. hole to 3700-m true vertical depth. The lithogy of the section is variable, beginning with a soft claystone, followed by several sandstone formations, an 1100-m interbedded sandstone and claystone interval, a 125-m hard carbonate, and 50m of softer claystone before the casing point. The challenges presented in recent offset wells included high stick/slip, high levels of drill bit cutting structure wear and drill bit body erosion. Polycrystalline diamond compact (PDC) bit designs utilized in recent offsets varied from six to nine blades, with the interval requiring two or three bits to complete the interval.\u0000 Based on results from other challenging offshore applications, including improved durability and drilling dynamics, the next-generation PDC and roller-cone hybrid drill bit (hybrid) with improved design features was selected for the application. Improved design features included a new increased blade count concept, combined with a sharp and dense roller-cone cutting structure.\u0000 The application of the next-generation hybrid drill bit design delivered a reduction in drilling time and an improvement to drilling dynamics compared to offset wells drilled with conventional technology. Compared to the best offset well drilled in 17.5-in. hole a reduction in total drilling time of 59.4hrs (31%) was achieved. The reduction in drilling time resulted from both an increase in on bottom ROP of 32% and the removal a bit trip (19 hours) due to the interval being drilled in one run for the first time. Associated with the reduced drilling time, improvements in drilling dynamics were observed with stick/slip reduced by 73%.\u0000 This paper illustrates the study of the application, applied learnings from new technology developments in hybrid technology evolution, and the subsequent improvements in drilling dynamics that resulted in improved penetration rates and cost savings in this challenging application.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131924754","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":"From Prospect to Life of Field Service – The Role and Impact of Well Installation/ Intervention from a Subsea EPC Contractor's Point of View","authors":"L. Bay","doi":"10.4043/29492-MS","DOIUrl":"https://doi.org/10.4043/29492-MS","url":null,"abstract":"\u0000 Being a global Subsea and Topside EPC contractor is often synonym with having an extensive portfolio of subsea production system solutions, sometimes including installation and well intervention systems such as landing string systems, riser based intervention systems and riser less intervention systems. However, unlike companies who focus specifically on subsea well intervention, and typically targets life of field opportunities, these EPC contractors might have this technology is in-house which enables cross discipline discussions already during concept studies and Front End Engineering Design studies (FEEDs). This enables contractor and client to select suitable technology not only based on equipment functionality and hardware cost, but highlights the operational impact such selections have both regarding installation of the equipment, and well intervention service throughout the lifetime of the field.\u0000 In a reference project a global EPC company is the main contractor for the engineering, procurement, construction and installation of the Subsea Production System (SPS) equipment in projects related to two large field developments West of Africa for a major operator. A total of 92 vertical subsea x-mas trees (VXTs) was awarded between 2013-2014 designed to be installed in depths down to approximately 2000m. In this case it was decided to install the tubing hangers using simplified landing string technology, while a riser based light intervention system was selected to provide flexible options for VXT installation, well clean-up/ flow back and life of field well intervention. A cross-vendor workover control system was selected to be used in both installation and intervention modes, allowing the operator to perform well interventions on existing subsea infrastructure in the region with 3rd party XT vendors, in addition to the planned field developments.\u0000 This paper will discuss how an EPC contractor can exploit the benefits of being both a subsea EPC contractor and an installation and well intervention service provider. The referenced project will be used as a case study, starting with the early phase studies, to show how decisions related to installation and intervention systems can greatly impact the XT selection and life of field strategy, and hence the configuration of the overall SPS and corresponding tooling. The philosophies around rig related services such as this connects the operator spend on SPS, SURF and drilling scope, and can greatly impact the overall project economics due to synergies across the distinct areas of investment. Furthermore, the paper discusses the importance of having a holistic approach when considering an intervention system for late life management, why it is beneficial to discuss such strategies at an early stage, and the benefits this brings to the end client over time.","PeriodicalId":214691,"journal":{"name":"Day 4 Thu, May 09, 2019","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128277017","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}