Oil Containment by Floating Boom under Wave-Current Coupling Conditions III: Prediction on Failure Velocity

2014 ◽  
Vol 955-959 ◽  
pp. 1491-1495
Author(s):  
Xing Feng ◽  
Wan Qing Wu ◽  
Gui Feng Yu
Keyword(s):  
Numerical Simulation ◽  
Companion Paper ◽  
Experimental Platform ◽  
Oil Boom ◽  
Coupling Conditions ◽  
Wave Parameters ◽  
Oil Spill Response ◽  
Current Coupling ◽  
Oil Density ◽  
Detailed Derivation

The numerical simulation of oil containment by floating boom under wave-current coupling conditions is presented in a companion paper. The present paper focuses on the use of the numerical experimental platform developed by FENG and WU for the prediction of oil containment failure velocity of floating boom under wave-current coupling conditions. Detailed derivation processes about the containment failure velocity formula are provided. The effects of oil parameters, wave parameters and oil boom parameters on oil containment failure velocity receive particular attention, and the influences of some of these parameters such as oil density, boom draft are quantified. The prediction model can provide an economic, convenient method for oil spill response.

Oil Containment by Floating Boom under Wave-Current Coupling Condition II: Containment Failure

2013 ◽  
Vol 734-737 ◽  
pp. 1420-1424
Author(s):  
Qing Gong Zheng ◽  
Xing Feng ◽  
Wan Qing Wu
Keyword(s):  
Companion Paper ◽  
Coupling Condition ◽  
Experimental Platform ◽  
Wave Parameters ◽  
Current Coupling ◽  
Oil Density ◽  
The Relationship

The numerical experimental platform of oil containment by floating boom under combined wave and current conditions was presented in a companion paper. The present paper focuses on the application of the platform that numerically predicts the relationship between oil containment failure velocity and wave parameters, oil parameters and boom drafts. The effects of oil density and wave parameters on oil containment failure velocity receive particular attention, and the influence of other parameters such as initial oil volume and boom draft are also quantified.

Numerical modeling of floating oil boom motions in wave-current coupling conditions

2017 ◽  
Vol 16 (4) ◽  
pp. 602-608 ◽  
Author(s):  
Yang Shi ◽  
Shaowu Li ◽  
Huaqin Zhang ◽  
Shitao Peng ◽  
Hanbao Chen ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Oil Boom ◽  
Coupling Conditions ◽  
Current Coupling

Numerical Simulation of the “Floating Spiral” Pipeline Installation Procedure: Second Stage, Spiral Transportation, Behavior Under Waves

2008 ◽  
Author(s):  
Bruno Martins Jacovazzo ◽  
Fabri´cio Nogueira Correˆa ◽  
Carl Horst Albrecht ◽  
Breno Pinheiro Jacob ◽  
Fernando Gomes da Silva Torres ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Optimal Control ◽  
Environmental Conditions ◽  
Companion Paper ◽  
Time Constraints ◽  
Second Stage ◽  
Parametric Studies ◽  
Large Length ◽  
Transportation Behavior ◽  
Flat Spiral

The Floating Spiral pipeline installation method consists basically in winding the pipeline into a huge floating spiral, and towing this assembly to the installation site, where the spiral is then unwound and lowered to the seabed. In this method the pipeline is fabricated onshore, as the spiral is created, under well controlled conditions and relatively relaxed time constraints. Therefore the welds can be better inspected, which allows for optimal control of quality in pipeline manufacturing. The first stage of the installation process by this method consists in setting the pipeline afloat and winding it elastically to form a large flat spiral. This stage is studied in a companion paper [1], to be also presented at IPC2008. The second stage consists in towing the floating spiral pipeline employing standard tugboats before laying it at the installation site. The objective of this work is, therefore, to present results of parametric studies for a large length pipeline at this second stage of the Floating Spiral method. The focus now is in the pipeline behavior under wave environmental conditions during transportation. Several numerical simulations are performed and the results are discussed and compared.

HISTORICAL BUILDUP OF OIL SPILL RESPONSE CAPABILITY IN JAPAN

1993 ◽  
Vol 1993 (1) ◽  
pp. 39-43
Author(s):  
Sakae Shirai
Keyword(s):  
Oil Spill ◽  
Response Force ◽  
Disaster Prevention ◽  
International Convention ◽  
Oil Boom ◽  
Oil Storage ◽  
Oil Spill Response ◽  
The Government ◽  
Prevention Law ◽  
Response Capability

ABSTRACT With the large oil spill that occurred in 1971 as an impetus, Japan's Maritime Pollution and Disaster Prevention Law was amended in 1973 and subsequently in 1976. The amendments required owners of vessels and petroleum facilities to retain designated quantities of oil boom, sorbent, dispersant, and other items to minimize impact from spills. A large oil spill caused by a ruptured crude oil storage tank in 1974 led to the enactment of additional legislation: the Petroleum Complex Disaster Prevention Law. Under this, petroleum facilities are required to maintain designated quantities of oil boom, oil boom deploying vessels, skimming boats, and the like. These legislative measures, together with voluntary efforts, have contributed to a sound buildup of the nation's oil spill response force. However, the response capability including stockpiled materials and equipment has been designed primarily to cope with incidents in closed waters such as inland seas, bays, and ports, and hence not for a oil spill in open seas as large as that from the Exxon Valdez. As one of the measures under the 1990 International Convention for Oil Spill Preparedness, Response and Cooperation, the Government of Japan has entrusted the Petroleum Association of Japan with an oil spill response capability reinforcement project to cope with a large oil spill should one occur in Japanese waters or nearby seas. Under the scheme, during the 5 year period beginning in 1991, the Petroleum Association of Japan is scheduled to build up, using subsidies from the government, stockpiles of cleanup equipment and materials and to augment the existing response capability.

scholarly journals Спиральные, концентрические и химерные волновые структуры в двумерном ансамбле нелокально связанных генераторов Ван дер Поля

2019 ◽  
Vol 45 (13) ◽  
pp. 40
Author(s):  
А.В. Бух ◽  
В.С. Анищенко
Keyword(s):  
Numerical Simulation ◽  
Van Der Pol ◽  
Nonlocal Coupling ◽  
Coupling Conditions ◽  
New Type

In the work, dynamics of a 2D ensemble of nonlocally coupled van der Pol generators are investigated using numerical simulation. The possibility of implementing regular spiral and target waves is established. The effect of the appearance of a new type of chimera structure, realized on the basis of target waves in nonlocal coupling conditions, is shown.

Development of a Training Simulator for Oil Spill Response

2014 ◽  
Author(s):  
Vinicius L. Vileti ◽  
Albino Ribeiro Neto ◽  
Joel S. Sales ◽  
Paulo de Tarso T. Esperança ◽  
Sergio H. Sphaier ◽  
...  
Keyword(s):  
Oil Spill ◽  
Training System ◽  
Simplified Model ◽  
Training Simulator ◽  
Morison Equation ◽  
Oil Boom ◽  
Oil Spill Response ◽  
Verification Process ◽  
Lumped Masses

The paper describes the development of a training simulator for boats used on Oil Spill response at sea. The simulator models the dynamics of tug boats pulling an oil boom under waves, wind and current. The boom is modeled as a flexible line connected by lumped masses and its flotation characteristics and loads are calculated by Morison equation. A simplified model is used to simulate the oil itself and its interface with the boom line. The verification process was applied and its outcomes are discussed. Also, some case study scenarios are presented and the results are used to evaluate the applicability of the simulator as a training system.

Use of the Moving Frame Method in Dynamics to Model Gyroscopic Control of Small Crafts at Sea: Theory — Part 1

2017 ◽  
Author(s):  
Joakim Nyland ◽  
Håkon Teigland ◽  
Thomas J. Impelluso
Keyword(s):  
Numerical Simulation ◽  
Large Scale ◽  
Equations Of Motion ◽  
Companion Paper ◽  
Cross Product ◽  
Moving Frame ◽  
3D Analysis ◽  
Active System ◽  
Moving Frame Method ◽  
Frame Method

This paper presents new method in dynamics — the Moving Frame Method (MFM) — and uses it to address a challenge faceing Norwegian shipping. Large offshore renewable energy investments require the use of maintenance boats to keep them in operable conditions. Unfortunately, due to rough seas in some project locations, the transferring of crew members from vessel to turbine or platform is fraught with safety concerns. These concerns can be alleviated by controlling the motion of the transfer vessel. This research studies an add-on stability system for marine vessels to ease the process of offshore platform maintenance and crew member safety. Specifically, this research concerns an internal active system — an active gyroscopic stabilizer — and a more powerful method of theoretical and computational mechanics. This paper derives the equations of motion of a model system equipped with dual gyroscopic stabilizers, using the MFM. The equations of motion are numerically solved to obtain a numerical simulation. The method exploits a variational principle with a restricted variation of the angular velocity. The MFM simplifies dynamics, enables a consistent notation, from 2D to 3D analysis and exploits matrix algebra in lieu of the vector cross product. Finally, in a companion paper to this one, the mathematical model and the numerical simulation is verified with experiments conducted in a large-scale wave tank.

A High-Resolution Modeling Study of the 24 May 2002 Dryline Case during IHOP. Part I: Numerical Simulation and General Evolution of the Dryline and Convection

2006 ◽  
Vol 134 (1) ◽  
pp. 149-171 ◽  
Author(s):  
Ming Xue ◽  
William J. Martin
Keyword(s):  
Numerical Simulation ◽  
Boundary Layer ◽  
High Resolution ◽  
Companion Paper ◽  
Horizontal Resolution ◽  
Initial Condition ◽  
Moist Convection ◽  
Convective Initiation ◽  
Deep Moist Convection ◽  
Localized Forcing

Abstract Results from a high-resolution numerical simulation of the 24 May 2002 dryline convective initiation (CI) case are presented. The simulation uses a 400 km × 700 km domain with a 1-km horizontal resolution grid nested inside a 3-km domain and starts from an assimilated initial condition at 1800 UTC. Routine as well as special upper-air and surface observations collected during the International H2O Project (IHOP_2002) are assimilated into the initial condition. The initiation of convective storms at around 2015 UTC along a section of the dryline south of the Texas panhandle is correctly predicted, as is the noninitiation of convection at a cold-front–dryline intersection (triple point) located farther north. The timing and location of predicted CI are accurate to within 20 min and 25 km, respectively. The general evolution of the predicted convective line up to 6 h of model time also verifies well. Mesoscale convergence associated with the confluent flow around the dryline is shown to produce an upward moisture bulge, while surface heating and boundary layer mixing are responsible for the general deepening of the boundary layer. These processes produce favorable conditions for convection but the actual triggering of deep moist convection at specific locations along the dryline depends on localized forcing. Interaction of the primary dryline convergence boundary with horizontal convective rolls on its west side provides such localized forcing, while convective eddies on the immediate east side are suppressed by a downward mesoscale dryline circulation. A companion paper analyzes in detail the exact processes of convective initiation along this dryline.

scholarly journals A geometrical framework for f –statistics

2020 ◽  
Author(s):  
Gonzalo Oteo–García ◽  
José–Angel Oteo
Keyword(s):  
Numerical Simulation ◽  
Phylogenetic Tree ◽  
Distance Matrix ◽  
Fixation Index ◽  
Population Admixture ◽  
Admixture Proportion ◽  
Genetic Distance Matrix ◽  
Detailed Derivation ◽  
Coalescence Times ◽  
F Statistics

AbstractA detailed derivation of the f–statistics formalism is made from a geometrical framework. It is shown that the f–statistics appear when a genetic distance matrix is constrained to describe a four population phylogenetic tree. The choice of genetic metric is crucial and plays an outstanding role as regards the tree–like–ness criterion. The case of lack of treeness is interpreted in the formalism as presence of population admixture. In this respect, four formulas are given to estimate the admixture proportions. One of them is the so–called f4–ratio estimate and we show that a second one is related to a known result developed in terms of the fixation index FST. An illustrative numerical simulation of admixture proportion estimates is included. Relationships of the formalism with coalescence times and pairwise sequence differences are also provided.

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