The SPE has split the former "Management & Information" technical discipline into two new technical discplines:
- Data Science & Engineering Analytics
The SPE has split the former "Management & Information" technical discipline into two new technical discplines:
|Theme||Visible||Selectable||Appearance||Zoom Range (now: 0)|
_ Ship maneuvring simulators are a useful tool for the design of inland waterways and for training of skippers. The realism of the maneuvring prediction is a key success factor. In this paper, a 6 DOF (degrees of freedom) maneuvring model is presented which is able to predict the maneuvring behavior of push convoys in different, rigidly connected configurations (number of barges, draft of the barges, and position of the pusher) and for different water depths. The coefficients of this maneuvring model have been determined based on captive model tests and the realism is exemplified with a number of fast time simulation runs, including the turning on the spot of a convoy by means of uncoupled control of rudders and propellers. Final validations were performed during real-time simulation runs with experienced skippers. Introduction Knowledge on the maneuvring prediction of inland vessels is a key factor to determine the navigability of the waterways, especially when their water depth is limited (shallow water). The quality and accuracy of mathematical models require a continuous improvement. Push convoys operating in shallow water are intensively used performing long trips or elaborated maneuvers such as turning from a river into a harbor, turning on the spot, and astern sailing. An appropriate modeling of their maneuvring capacity requires a mathematical model able to operate in four quadrants (ahead or astern motion, combined with ahead or astern propulsion). In literature, papers which deal with the creation of reliable mathematical models for this type of inland vessels and their applications are rather scarce.
"In offshore and coastal engineering, metocean refers to the syllabic abbreviation of meteorology and (physical) oceanography" (Wikipedia). Metocean research covers dynamics of the oceaninterface environments: the air-sea surface, atmospheric boundary layer, upper ocean, the sea bed within the wavelength proximity (~100 m for wind-generated waves), and coastal areas. Metocean disciplines broadly comprise maritime engineering, marine meteorology, wave forecast, operational oceanography, oceanic climate, sediment transport, coastal morphology, and specialised technological disciplines for in-situ and remote sensing observations. Metocean applications incorporate offshore, coastal and Arctic engineering; navigation, shipping and naval architecture; marine search and rescue; environmental instrumentation, among others. Often, both for design and operational purposes the ISSC community is interested in Metocean Extremes which include extreme conditions (such as extreme tropical or extra-tropical cyclones), extreme events (such as rogue waves) and extreme environments (such as Marginal Ice Zone, MIZ). Certain Metocean conditions appear extreme, depending on applications (e.g.
UK infrastructure that regasifies liquefied natural gas (LNG) for further transit via pipeline to the Netherlands and Belgium is emerging as a key element in Europe's evolving strategy to reduce its dependence on Russian gas this year by two-thirds. In its annual Summer Gas Outlook published on 14 April, the UK's National Grid plc, a British multinational electricity and gas utility company, noted that the UK will increase its gas exports over the next 6 months to help Europe fill its gas storage sites ahead of next winter. European gas storage was at 27% at the end of this winter as compared to 30% the same time a year ago. The UK has been a net importer of gas since 2005, covering 50% of demand with its own production from the North and Irish Seas plus associated petroleum gas from oil fields. Any surplus gas in the system can then be exported to Europe via the BBL pipeline to the Netherlands (Bacton to Balgzand) or through the Interconnector pipeline to Belgium (Bacton to Zeebrugge.)
Moussawi, Marwa (Université Catholique de Louvain) | Basnet, Samip (Université Catholique de Louvain) | Gil, Eduardo Cortina (Université Catholique de Louvain) | Demin, Pavel (Université Catholique de Louvain) | Gamage, Ran M. I. D. (Université Catholique de Louvain) | Giammanco, Andrea (Université Catholique de Louvain) | Karnam, Raveendrababu (Ghent University) | Samalan, Amrutha (Ghent University) | Tytgat, Michael (Ghent University)
We are developing a portable cosmic-ray muon detector for usage in confined environments, including use cases in exploration geophysics. Our project aims at a compact, autonomous, modular and versatile set-up based on Resistive Plate Chambers.
Abstract When exposed to harsh conditions like sour environment, the resistance of low carbon line pipe steels to hydrogen embrittlement is of the upmost importance. There are several factors that are playing a role on the sour resistance of line pipe steels. The control of secondary phase inclusions is one of the most known factors. For example, elongated MnS or hard non-metallic inclusions like Al2O3 act as stress concentrators via the accumulation and recombination of hydrogen atoms. A banded microstructure like ferrite-perlite bands is also known to increase the susceptibility to hydrogen cracking. And finally, the corrosion of the steel at the steel-fluid interface plays also a role on the sour performances and is often less discussed in the literature than the previous two parameters. This paper highlights the importance of the corrosion layer developed during sour exposure on the overall Sulfide Stress Cracking (SSC) resistance of 4 line pipe steels designed as per API 5L annex H. The impact of Ni and Cr alloying is investigated here in terms of diffusible hydrogen and surface evolution. The former is studied via permeation and interrupted testing with direct hydrogen measurements while the latter is studied via EPMA, SEM and XRD. The overall sour performances are evaluated by four-point bending and uni-axial constant load tests following NACE TM0316 and NACE TM0177 standards. In this study, Ni and Cr alloying have different effects. Nickel alloying improves the compacity and the coverage of the corrosion layer which acts as a barrier by limiting the hydrogen concentration inside the steel and improves the overall sour resistance. However, this was not observed in the Cr alloyed steel. With the test conditions of the present study, the Cr-alloyed steel did not develop a homogeneously distributed iron sulfide corrosion layer during sour exposure which resulted in a hydrogen level into the metal nearly 5 times higher than the Ni-alloyed steel after 30 days and failures in the SSC A tests.
Abstract The article presents a theoretical model of filtering the wave spectrum by an approach channel, based on the refractive reflection of waves. Was performed an analytical, experimental, and numerical study of waves in the channel. When the waves pass through the channel, some frequency components of the wave spectrum are reflected from the channel. This trend was reflected in numerical and analytical studies, and the calculation results showed good convergence. INTRODUCTION Innovations in marine technology have led to an increase in maritime traffic worldwide, which has led to a significant increase in the average size of ships. This trend has led to the need to expand port facilities and increase the size of approach channels. Modern practice in the construction of navigation channels shows that they can have a significant length, width, and depth. They can have a significant impact on the propagation of waves in the channel zone and require special research, the development of appropriate models and calculation methods. Correct estimates of the wave parameters in the area of the navigation channel affect the loads acting on the port's protective structures, and on the waves penetrating the port's water area, affecting the conditions for mooring ships at the berths. The parameters of waves suitable for coastal hydraulic structures are determined based on field observations, laboratory modeling, computational methods, and numerical studies. The problem of the impact of the underwater channel on the waves is a specific problem in which the waves can be amplified on the channel and can be weakened. This problem has been investigated by several scientists [Beltrami et al., 2003; Dusseljee et al., 2012; Dusseljee et al., 2014; Gruwez at el., 2011; Gruwez, Bolle, Verwaest, 2012], but most of the research relates to regular waves. At the same time, the problem of wave propagation over an underwater channel requires considering the irregular nature of wind waves.
ExxonMobil expects a new $1 billion fuel upgrading unit at its Antwerp refinery to be fully operational in the first half of next year, the company said on 28 November. The delayed coker unit, part of a $1 billion investment announced in 2014, will enable the 320,000-B/D refinery to upgrade high-sulphur fuel into various types of diesel, including the variant mandated by new laws governing shipping fuels. The company announced the investment during a particularly tough period for European refining, when margins were near multiyear lows and demand in the region appeared to be in permanent decline. However, refining profits have since rebounded strongly. An Exxon spokeswoman said the company plans to complete construction "towards early 2018."
Abstract Chalk formations have been investigated for many years because of their interest in several engineering applications like oil and gas production, offshore engineering, water resources and environmental issues, foundations and piling, geological hazards and tunnelling. Recently there has been a growing interest for connecting the engineering behaviour of such rocks to their geological history. The current study focusses on three cored drillholes that were drilled in chalk formations of the Mons Basin (Belgium). This basin is a 300-m-thick pile of Meso-Cenozoic sediments that accumulated in a small but actively subsiding area mainly during the Cretaceous. A geological logging of the cores provides a detailed description of the lithologies, with their specific sedimentary and tectonic features. Distinct lithotypes are identified, including white chalk, cyclic chalk, glauconitic chalk or burrowed chalk. Simultaneously, a systematic testing program was conducted in laboratory to determine the engineering properties of the chalk: dry and saturated densities, unconfined compression strength (UCS), Young's modulus and Brazilian tensile strength (BTS). The high sampling rate (e.g. almost every 2m for UCS with a total of 200 tests) allowed a statistical analysis of petrophysical and mechanical properties in connection with the geological formations. The analysed samples are typically soft rocks, with a strength ranging from 2.6 to 14.1 MPa. Some properties tend to increase with the depth (density, UCS). However, the nature of the geological formations, resulting from various depositional environments and diagenetic histories influences the mechanical behaviour of chalk. 1 Introduction Chalk formations have been investigated for many years because of their interest in several engineering applications like oil and gas production, water resources and environmental issues, geological hazards, etc. Recently there has been a growing interest for connecting the engineering behaviour of such rocks to their geological history. Particularly, Descamps et al. (2017) studied a wide variety of NW European chalk samples and showed that diagenesis strongly affects their mechanical behaviour. The current study focusses on Cretaceous formations of the Mons Basin (Belgium). Three cored drillholes were performed on the northern edge of the basin, reaching depths of 146m, 89m and 139m. Geological logging provided detailed descriptions of the lithologies, with their specific sedimentary and tectonic features. Simultaneously, petrophysical and mechanical properties were determined in laboratory.
Abstract The Trou Loulou is an old underground soft carbonate quarry located in Eastern Belgium. This shallow depth room-and-pillar quarry was mined out from the 16th century for building stone. Now, it is considered as a cultural heritage. In the same area, an open-pit quarry is currently mining carbonated rocks for cement production. The Trou Loulou is located in the extension of this open-pit quarry. Therefore, a stability study was required for determining the security distance between both sites in order to preserve this heritage when the open-pit comes closer to it. In this paper, we first describe the geological context. A conceptual model is derived from 2D and 3D surveying of the site. In situ and laboratory mechanical characterizations are performed and a stability analysis is proposed using 2D finite element modelling. Progressive simulation of the open-pit quarry shows the occurrence of localized roof failure. 1 Introduction Carbonated rocks have been mined out in Eastern Belgium for several centuries. In this study, we focus on two sites: an underground quarry and an open-pit one. First, tuffeau was used since the 16 or 17 century as a building stone. For this purpose, a shallow depth room-and-pillar quarry was developed, following an irregular pattern, using peaks and saws for cutting the rock. This activity led to 12km of galleries, containing many historical traces (drawings, engravings, etc.) and which later also served as a refuge during the war. This site is named "Trou Loulou" and is now considered as a cultural heritage. In the last decades, open-pit quarries developed in the same area for cement production and are still expanding. Particularly, this study deals with the extension of one quarry in the direction of the Trou Loulou underground cavity (Figure. 1, left). In order to plan its future activities and guarantee the preservation of the historical site, the cement producer wanted to determine the security distance to keep between the current open-pit quarry and the Trou Loulou.
ABSTRACT In this paper, the hydrodynamic performances of a container ship in cross flows during lateral motions are numerically investigated. The numerical error caused by the grid discretization is evaluated by a convergence study. The lateral force, yaw moment, roll moment, as well as dynamic sinkage and trim are compared with available benchmark test data. In addition, effects of the domain width, water depth, ship speed on the hydrodynamic quantities are studied. The numerical results indicate that the lateral force is much more pronounced than other hydrodynamic quantities due to the massive cross-flow effects, and the free-surface effect is found to be important in shallow waters. INTRODUCTION When navigating in harbor areas, a ship very often has to be operated in lateral motions at large drift angles where massive cross flows may be generated around the hull. Typical examples are berthing, unberthing or turning manoeuvres. In these cases, hydrodynamic performances of the ship are more complex comparing to the straight-head navigation as the cross flows introduce more pronounced flow separations, vortices around the ship. More importantly, the restricted waters in harbors further aggravate the problem. The shallow-water or bank effects induced by the limited gaps between the ship and seabed or bank sides of the pier give rise to additional hydrodynamic forces and moments acting on the hull, resulting in potential collision or grounding accidents. The latter is closely related to a sudden change of the sinkage and trim, which is the so-called "squat" phenomenon. As a consequence, the manoeuvring operation of these ships in restricted waterways of harbors, especially the large ships, tends to be more difficult, and their navigation problems become increasingly notable. Traditionally, the investigation of ship manoeuvring performance in shallow or confined waters mainly lied on the model tests utilizing experimental techniques (termed as EFD, Experimental Fluid Dynamics methods), which were widely used in decades (Verwilligen et al., 2018; Tello Ruiz et al., 2017; Vantorre et al., 2016; Lataire et al., 2009; Eloot et al., 2006; etc.). From the model tests, hydrodynamic performances in standard ship manoeuvres can be measured and analyzed. However, the tests for ship berthing or unberthing are very limited. Most of the tests were made for commercial hull forms and primarily concerned the performances of the propellers or thrusters as crucial auxiliary devices during the berthing or unberthing operations (Abramowicz-Gerigk, 2008; Yoo et al., 2006). Lee et al. (2011) performed a series of experiments to investigate the hydrodynamic forces of a twin-screw ferry influenced by the water depth or the distance between the ship and the quay. It was found that the fluid dynamics during the unberthing is a very complicated phenomenon and requires a vast number of experiments with various environmental and operational parameters. With regard to the tests for ship hydrodynamic performances in pure cross flows, the available contribution is found in the benchmark tests conducted by Delefortrie et al. (2012) for the SIMMAN2014 (Workshop on Verification and Validation of Ship Manoeuvring Simulation Methods), where three model tests were conducted as additional tests for harbor manoeuvring data.