Numerical simulation study of oil diffusion at low tide near the port area of Ma’ao, Zhoushan

In this paper, the numerical hydrodynamic simulation has been carried out by using measured topographic data and related tidal information. The oil particle tracking module of MIKE21 is adopted to study the processes of drifting and turbulent diffusion of oil particles on the water surface, where four working conditions, namely, static wind, dominant wind direction, maximum wind direction and most unfavourable wind direction, are applied. Results show that Xiushan Island will be the apparent ‘victim’ in the cases of oil spill in all wind directions. Meanwhile, due to the existence of Changbai Island and Xiushan Island, the diffusion process of oil particles is obviously retarded to impact the protected marine areas.

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Numerical Simulation of Dispersed Multiphase Flow Based on a Particle Tracking Method. 1st Report. Numerical Method and Application to Laminar Bubbly Upflow in a Duct.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.62.2558 ◽

1996 ◽

Vol 62 (599) ◽

pp. 2558-2564

Author(s):

Akio TOMIYAMA ◽

Hitoshi HIGAKI ◽

Iztok ZUN ◽

Akira SOU ◽

Tadashi SAKAGUCHI

Keyword(s):

Numerical Simulation ◽

Multiphase Flow ◽

Numerical Method ◽

Particle Tracking ◽

Tracking Method ◽

Particle Tracking Method

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“Numerical simulation of compaction-induced stress for the analysis of GRS walls under working conditions” by S. H. Mirmoradi and M. Ehrlich, Geotextiles and Geomembranes, 46 (2018), pp. 354-365

Geotextiles and Geomembranes ◽

10.1016/j.geotexmem.2018.04.016 ◽

2018 ◽

Vol 46 (6) ◽

pp. 913-914 ◽

Cited By ~ 4

Author(s):

Jonathan T.H. Wu ◽

Peter Hoffman ◽

Thang Q. Pham

Keyword(s):

Numerical Simulation ◽

Working Conditions ◽

Induced Stress

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Prefabricated Urban Underground Utility Tunnels: A Case Study on Mechanical Behaviour with Strain Monitoring and Numerical Simulation

Advances in Materials Science and Engineering ◽

10.1155/2021/5534526 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Yonggang Xiao ◽

Jubing Zhang ◽

Jie Cao ◽

Changhong Li

Keyword(s):

Numerical Simulation ◽

Working Conditions ◽

Failure Modes ◽

Mechanical Performance ◽

Low Cost ◽

Side Wall ◽

Operating Conditions ◽

Land Occupation ◽

Depth Analysis ◽

Simulation Results

The prefabricated urban utility tunnels (UUTs) have many advantages such as short construction period, low cost, high quality, and small land occupation. However, there is still a lack of in-depth analysis of the mechanical performance of the prefabricated urban utility tunnel (UUT) structure with bolted connections under different working conditions. In this paper, the force performance of a prefabricated UUT in Tongzhou District, Beijing, was studied under different working conditions using two methods: field monitoring and numerical simulation. The multichannel strain monitor was used for monitoring, and the internal wall concrete and bolt strain change data under the two conditions of installation and backfill were obtained. Combined with the construction process of the UUTs, a three-dimensional numerical model was established by COMSOL, where the build-in bolt assembly was used to simulate the longitudinal connection of the tunnel. The simulation results were compared with the measured data to verify the rationality of the computational model. The simulation results showed that the concrete and bolts on the inner wall of the tunnel work well under the two conditions of installation and backfilling; The deformation of the top plate of the prefabricated tunnel was approximately parabolic, with the largest vertical displacement (0.37 mm) in the middle and the most sensitive to the vertical load in the central part of the roof. The central portion of the side wall had the largest displacement (0.17 mm) in the inner concave. The tensile stress of bolt 3 increased the most (30.75 MPa) but was still much smaller than the yield strength of the bolt. The concrete and bolts of the UUT were found to work well through force analysis under operating conditions. In conclusion, analysis of structural forces and deformation failure modes will help design engineers understand the basic mechanisms and select the appropriate UUT structure.

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A message-passing, distributed memory parallel algorithm for direct numerical simulation of turbulence with particle tracking

Parallel Computational Fluid Dynamics 1995 ◽

10.1016/b978-044482322-9/50112-2 ◽

1996 ◽

pp. 473-480

Author(s):

P.K. Yeung ◽

Catherine A. Moseley

Keyword(s):

Numerical Simulation ◽

Direct Numerical Simulation ◽

Parallel Algorithm ◽

Particle Tracking ◽

Message Passing ◽

Distributed Memory

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Numerical Simulation and Analysis of the Arrangement of Wind Direction Meter for Wind Turbine

E3S Web of Conferences ◽

10.1051/e3sconf/201911802040 ◽

2019 ◽

Vol 118 ◽

pp. 02040

Author(s):

Zhipeng Xue ◽

Jie Fu ◽

Minmin Zhao

Keyword(s):

Numerical Simulation ◽

Numerical Analysis ◽

Wind Turbine ◽

Wind Direction ◽

Reference Point ◽

Measuring Equipment ◽

Flow Phenomenon ◽

Current Location ◽

Variation Characteristics ◽

Cfd Numerical Analysis

This paper performs CFD numerical analysis on the wind direction variation characteristics of the upper part of the platform under the running condition of the whole machine, and analyses whether the current location of the equipment is suitable for placing the wind direction measuring equipment and finding a better position in the area. The vicinity of the reference point is the area where the airflow is relatively intense, and the wind direction is complex and changeable. In-depth CFD research on this flow phenomenon can obtain an intuitive wind direction state and inherently subtle changes.

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Buried Depth of a Submarine Pipeline Based on Anchor Penetration

Journal of Marine Science and Engineering ◽

10.3390/jmse7080257 ◽

2019 ◽

Vol 7 (8) ◽

pp. 257

Author(s):

Xueyuan Zhu ◽

Qinglong Hao ◽

Jie Zhang

Keyword(s):

Numerical Simulation ◽

Penetration Depth ◽

Water Depth ◽

Calculation Method ◽

Water Surface ◽

Submarine Pipeline ◽

Projected Area ◽

Actual Measurement ◽

Calculation Results ◽

The Relationship

Anchor penetration is an important issue involved in the study of submarine pipeline damage accidents. To explore the penetration of a ship’s anchor under certain conditions, this study investigated the motion and force of an anchor and formulated a calculation method for the bottoming speed of an anchor. Meanwhile, the depth of anchor penetration was calculated under different conditions according to bottoming speed through programming. Finally, the reliability of the calculation method for the penetration depth was verified by comparing the actual measurement and the numerical simulation. On the basis of the findings, the calculation results were further analyzed, and conclusions were derived regarding the relationship between anchor mass, the horizontal projected area of the anchor, the anchor height on the water surface, and water depth. The conclusions provide suggestions for the application of anchor penetration in terms of seabed depth with certain reference values.

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A Simple Model for the Quantum Hydrodynamic Simulation of Electron Transport in Quantum Confined Structures in the Presence of Vortices

VLSI Design ◽

10.1155/2001/41084 ◽

2001 ◽

Vol 13 (1-4) ◽

pp. 237-244 ◽

Cited By ~ 2

Author(s):

J. R. Barker

Keyword(s):

Numerical Simulation ◽

Simple Model ◽

Quantum Transport ◽

Hydrodynamic Simulation ◽

Spatially Correlated ◽

Non Local ◽

Quantum Hydrodynamic ◽

String Representation ◽

Ray Trajectories ◽

Classical Particles

It is demonstrated that the ballistic quantum transport properties of an open quantum dot may be described by an ensemble of spatially correlated virtual classical particles moving within self-avoiding strings. The string paths correspond to ray trajectories. The strings exhibit the necessary properties of self-avoidance, interference and the non-local condition ∮mv · dr=nh. The formalism suggests that numerical simulation of quantum flows may be constructed ab initio by using the string representation.

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Experimental Research and Numerical Simulation on Grouting Quality of Shield Tunnel Based on Impact Echo Method

Shock and Vibration ◽

10.1155/2016/1025276 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10

Author(s):

Fei Yao ◽

Guangyu Chen ◽

Jianhong Su

Keyword(s):

Numerical Simulation ◽

Finite Element ◽

Working Conditions ◽

Acoustic Impedance ◽

Shield Tunnel ◽

Test Results ◽

Impact Echo ◽

Simulation Results ◽

The Impact ◽

Impact Echo Method

To identify shield grouting quality based on impact echo method, an impact echo test of segment-grouting (SG) test piece was carried out to explore effect of acoustic impedance of grouting layers and grouting defects on impact echo law. A finite element numerical simulation on the impact echo process was implemented. Test results and simulation results were compared. Results demonstrated that, under some working conditions, finite element simulation results and test results both agree with theoretical values. The acoustic impedance ratio of SG material influenced the echo characteristics significantly. But thickness frequency could not be detected under some working conditions because the reflected energy is weak. Frequency feature under grouting defects was more complicated than that under no grouting defects.

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