scholarly journals Geological controls on focused fluid flow in the Song Hong Basin, offshore Vietnam

2021 ◽  
Vol 62 (3) ◽  
pp. 37-45
Author(s):  
Keyword(s):  
Fluid Flow ◽  
Middle Miocene ◽  
Fluid Flows ◽  
Late Eocene ◽  
Significant Difference ◽  
Vertical Zone ◽  
Deep Source ◽  
Seismic Reflections ◽  
Seismic Lines ◽  
Intensive Development

This study uses 2D seismic lines located in the central Song Hong Basin, covering an area of c. 3900 m2, in the water depth of c. 100 m. Focused fluid flows are developed intensively and can be classified into two types: blow - out pipe and seepage pipe. They have similar seismic characteristics as a vertical zone of disturbed seismic reflections. The significant difference between them is the blow - out pipes associated with seafloor pockmarks and paleo - pockmarks which are absent in the seepage pipe. Besides, the scale of the blow - out pipe is larger, compared with the seepage pipe. The blow - out pipe is c. 500 m wide and 450÷3500 ms TWT; the seepage pipe is smaller scale, c. 200 m wide and 500 ms TWT. Blow - out pipe is rooting from the sequence just above the diapir or deformation unit or deep lacustrine mudstones from the Late Eocene to Oligocene, and marine mudstones from the Early to Middle Miocene. The seepage pipe is rooting from the sequence above the diapir. The focused fluid flow is supposed to be controlled by the overpressured deep source layers and passive diapirism. The occurrence of focused fluid flow is an indicator for the active petroleum system in the study area. Intensive development of focused fluid flow proves a great hydrocarbon potential in the Song Hong basin.

Lattice-BGK Methods for Simulating Incompressible Fluid Flows

1997 ◽  
Vol 08 (04) ◽  
pp. 793-803 ◽  
Author(s):  
Yu Chen ◽  
Hirotada Ohashi
Keyword(s):  
Fluid Flow ◽  
Incompressible Fluid ◽  
Poisson Equation ◽  
General Model ◽  
Incompressible Flows ◽  
Fluid Flows ◽  
Incompressible Limit ◽  
Numerical Example ◽  
Incompressible Fluid Flows

The lattice-Bhatnagar-Gross-Krook (BGK) method has been used to simulate fluid flow in the nearly incompressible limit. But for the completely incompressible flows, two special approaches should be applied to the general model, for the steady and unsteady cases, respectively. Introduced by Zou et al.,1 the method for steady incompressible flows will be described briefly in this paper. For the unsteady case, we will show, using a simple numerical example, the need to solve a Poisson equation for pressure.

A Suction Device Using Air Under Pressure

1956 ◽  
Vol 23 (2) ◽  
pp. 269-272
Author(s):  
L. F. Welanetz
Keyword(s):  
Fluid Flow ◽  
Flow Rate ◽  
Fluid Flows ◽  
Central Hole ◽  
Fluid Flow Rate ◽  
Circular Plates ◽  
Suction Device ◽  
Holding Power ◽  
Plate Separation

Abstract An analysis is made of the suction holding power of a device in which a fluid flows radially outward from a central hole between two parallel circular plates. The holding power and the fluid flow rate are determined as functions of the plate separation. The effect of changing the proportions of the device is investigated. Experiments were made to check the analysis.

scholarly journals Numerical Investigation on Fluid Flow in a 90-Degree Curved Pipe with Large Curvature Ratio

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Yan Wang ◽  
Quanlin Dong ◽  
Pengfei Wang
Keyword(s):  
Fluid Flow ◽  
Internal Flow ◽  
Fluid Flows ◽  
Detached Eddy Simulation ◽  
Number Range ◽  
Curvature Ratio ◽  
Large Curvature ◽  
Curved Pipe ◽  
Eddy Simulation ◽  
Curved Pipes

In order to understand the mechanism of fluid flows in curved pipes, a large number of theoretical and experimental researches have been performed. As a critical parameter of curved pipe, the curvature ratioδhas received much attention, but most of the values ofδare very small (δ<0.1) or relatively small (δ≤0.5). As a preliminary study and simulation this research studied the fluid flow in a 90-degree curved pipe of large curvature ratio. The Detached Eddy Simulation (DES) turbulence model was employed to investigate the fluid flows at the Reynolds number range from 5000 to 20000. After validation of the numerical strategy, the pressure and velocity distribution, pressure drop, fluid flow, and secondary flow along the curved pipe were illustrated. The results show that the fluid flow in a curved pipe with large curvature ratio seems to be unlike that in a curved pipe with small curvature ratio. Large curvature ratio makes the internal flow more complicated; thus, the flow patterns, the separation region, and the oscillatory flow are different.

Grossplots: a Method for Estimating the Temperature State of the Earth and of Australia, Cretaceous to Middle Miocene

1997 ◽  
Vol 45 (3) ◽  
pp. 359 ◽  
Author(s):  
L. A. Frakes
Keyword(s):  
Middle Miocene ◽  
Global Climate ◽  
Interval Data ◽  
Late Eocene ◽  
Space Distribution ◽  
Mean Annual Temperature ◽  
The North ◽  
Early Oligocene ◽  
Time Space ◽  
Temperature State

Grossplots are compilations of globally distributed palaeotemperature data onto latitude versus age plots, which are then contoured. The results specifically show the distribution of temperature over the globe and its variations over the Cretaceous to Middle Miocene interval. Data for continents and oceans are plotted separately in this investigation, and each such grossplot is in accord with the known climate changes of this time. The general scarcity of quantitative palaeotemperature information for Australia can be rectified by deriving, from the global continental grossplot, the relationship between mean annual temperature and latitude. When these are applied to the latitude band progressively occupied by Australia, the following observations can be made: (1) during the Early Cretaceous, the south-east of the continent was subjected to freezing wintertime temperatures; (2) peak warming of northern Australia was attained in the Turonian–Santonian, but this was followed by cooling later in the Cretaceous; (3) Early Tertiary warming until the Late Eocene particularly affected the northern half of the continent, but this region then underwent the most severe cooling in the Early Oligocene; (4) subsequently, the whole of the continent cooled uniformly from conditions only slightly warmer than at present. Despite Australia’s equatorward march, the Late Cretaceous to Palaeocene climates of the continent have been influenced more effectively by changes in the global climate state. However, global cooling since the Eocene has been less effective than drift in controlling the warming climate of Australia. The time–space distribution of precipitation over Australia is estimated from the global relationship between terrestrial temperature and rainfall. The Eocene experienced the heaviest rainfall (> 1560 mm year-1, in the north only), and the Eocene to Middle Miocene experienced moderately high rates (> 500 mm year-1 in the northern three-quarters of the continent). Tertiary brown coals in southern regions were formed in proximity to areas of high rainfall. Continentwide low rates (< 500 mm year-1; semi-arid) are suggested for the Cretaceous, except for wet conditions in the north during the Albian–Santonian and the Late Maastrichtian. Estimates of precipitation are subject to factors such as continentality and location of moisture sources, which cannot be evaluated at present.

Distinguishing tectonic versus climatic forcing on landscape evolution: An example from SE Tibetan Plateau

2020 ◽  
Vol 133 (1-2) ◽  
pp. 233-242 ◽  
Author(s):  
Fangbin Liu ◽  
Martin Danišík ◽  
Dewen Zheng ◽  
Kerry Gallagher ◽  
Junsheng Nie
Keyword(s):  
Tibetan Plateau ◽  
Middle Miocene ◽  
Asian Summer Monsoon ◽  
Late Eocene ◽  
Crustal Shortening ◽  
Lateral Extrusion ◽  
Granite Belt ◽  
Cooling Phase ◽  
Forcing Mechanisms ◽  
Exhumation History

Abstract Distinguishing climate from tectonic forcing in shaping the Earth’s surface has been a long-standing issue in the Earth sciences. Great debate exists regarding when and how the SE Tibetan Plateau achieved its current low-relief topography, and both lateral extrusion and lower crust flow have been proposed as the dominant mechanism. Reconstruction of the exhumation history of the SE Tibetan Plateau is key to understanding these formation processes and resolving the significance of different forcing mechanisms. Here we report zircon and apatite (U-Th)/He ages from steep transects across the Lincang granite belt of the SE Tibetan Plateau. Our results reveal a two-stage exhumation history during the Cenozoic with rapid cooling phases in the late Eocene and the middle Miocene. In the late Eocene, the climate was generally dry and there is plenty of evidence for increased extrusion and upper crustal shortening. We suggest tectonic processes are responsible for the first inferred cooling. In contrast, the Asian summer monsoon precipitation increased during the middle Miocene, and we posit the middle Miocene cooling phase records a phase of rapid river incision triggered by the intensified precipitation and associated fault movements. The results are consistent with recent paleo-altimetry work in this region suggesting that the present-day topography of the SE Tibetan Plateau had been largely constructed by the late Eocene. Together, these data suggest that extrusion and/or upper crustal shortening setup the first order topography of the SE Tibetan Plateau, which was then modified by climate-triggered fluvial incision and feedbacks initiated in the middle Miocene.

Influence of Viscoelasticity on Turbulent Flow Over a Backward-Facing Step

2015 ◽  
Author(s):  
Akito Ikegami ◽  
Takahiro Tsukahara ◽  
Yasuo Kawaguchi
Keyword(s):  
Fluid Flow ◽  
Turbulent Flow ◽  
Newtonian Fluid ◽  
Expansion Ratio ◽  
Weissenberg Number ◽  
Recirculation Region ◽  
Viscoelastic Flows ◽  
Backward Facing Step ◽  
Mean Velocity ◽  
Significant Difference

We studied viscoelastic turbulent flow over a backward-facing step of the expansion ratio ER = 1.5 using DNS (direct numerical simulation) at a friction Reynolds number Reτ0 of 100. We chose the Giesekus model as a viscoelastic constitutive equation, and the Weissenberg number is Wiτ0 = 10 and 20. Visualized instantaneous vortices revealing that a few vortices occur only above the recirculation regions in the viscoelastic fluid flow compared to those in the Newtonian flow. This phenomenon might be caused by the fluid viscoelasticity that would suppress the Kelvin-Helmholz vortex emanating from the step edge. The reattachment length from the step is 6.80h for the Newtonian fluid, 7.82h for Wiτ0 = 10, and 8.82h for Wiτ0 = 20, where h is the step height. In the mean velocity distributions normalized by maximum inlet velocity, we have observed no significant difference among the three fluids, except for region near the upper or bottom wall, i.e., the recirculation and recovery regions at the front and behind the reattachment point. The streamwise turbulent intensity u’rms is weaken in the recirculation region of the viscoelastic flows. In terms of v’rms, its magnitude in the recirculation region becomes largest in the case of Wiτ0 = 10, not for the Newtonian fluid flow or more viscoelastic case of Wiτ0 = 20.

scholarly journals Computer Modeling of Electromagnetic Fields and Fluid Flows for Edge Containment in Continuous Casting

2004 ◽  
Vol 127 (4) ◽  
pp. 724-730 ◽  
Author(s):  
Fon-Chieh Chang ◽  
John R. Hull
Keyword(s):  
Numerical Simulation ◽  
Fluid Flow ◽  
Liquid Metal ◽  
Eddy Currents ◽  
Stokes Equations ◽  
Fluid Flows ◽  
Experimental Results ◽  
Twin Roll Casting ◽  
Roll Casting ◽  
Twin Roll

A computer model was developed to predict eddy currents and fluid flows in molten steel. The model was verified by comparing predictions with experimental results of liquid-metal containment and fluid flow in electromagnetic (EM) edge dams (EMDs) designed at Inland Steel (Ispat Industries Ltd.) for twin-roll casting. This mathematical model can greatly shorten casting research on the use of EM fields for liquid metal containment and control. It can also optimize the existing casting processes and minimize expensive, time-consuming full-scale testing. The model was verified by comparing predictions with experimental results of liquid metal containment and fluid flow in EM edge dams designed at Inland Steel (Ispat Industries Ltd.) for twin-roll casting. Numerical simulation was performed by coupling a three-dimensional (3D) finite-element EM code (ELEKTRA) and a 3D finite-difference fluids code (CaPS-EM) to solve Maxwell’s equations, Ohm’s law, Navier-Stokes equations, and transport equations of turbulence flow in a casting process that uses EM fields. ELEKTRA is able to predict the eddy-current distribution and EM forces in complex geometry. CaPS-EM is capable of modeling fluid flows with free surfaces and dynamic rollers. The computed 3D magnetic fields and induced eddy currents in ELEKTRA are used as input to flow-field computations in CaPS-EM. Results of the numerical simulation compared well with measurements obtained from both static and dynamic tests.

scholarly journals Disks aligned in a turbulent channel

2015 ◽  
Vol 772 ◽  
pp. 1-4 ◽  
Author(s):  
Greg A. Voth
Keyword(s):  
Fluid Flow ◽  
Channel Flow ◽  
Particle Shape ◽  
Particle Density ◽  
Biological Fluid ◽  
Fluid Flows ◽  
Turbulent Channel Flow ◽  
Anisotropic Particles ◽  
Wide Range ◽  
Preferential Alignment

Anisotropic particles are suspended in a wide range of industrial, environmental and biological fluid flows. The orientations of these particles are sometimes randomized by turbulence, but often they are brought into preferential alignment by the fluid flow. In a recently published study, Challabotla, Zhao & Andersson (J. Fluid Mech., vol. 766, 2015, R2) performed the first numerical simulations of inertial disks in a turbulent channel flow. They find that disks can be made to preferentially align either parallel or perpendicular to the wall depending on the particle density. Particle shape also affects alignment, particularly for lower density particles, and the alignment of disks is quite different from the alignment of fibres.

Numerical Computation of Phase Separation in Two Fluid Flow

1984 ◽  
Vol 106 (2) ◽  
pp. 147-153 ◽  
Author(s):  
M. B. Carver
Keyword(s):  
Experimental Study ◽  
Fluid Flow ◽  
Phase Separation ◽  
Numerical Computation ◽  
Computational Analysis ◽  
Fluid Flows ◽  
Iterative Approach ◽  
Two Fluid

A new iterative approach is outlined for multidimensional computational analysis of two fluid flow. Parametric surveys are described to illustrate that the method rationally predicts separation of two fluid flows under gravitational and centrifugal influences. A comparison is made between behavior computed by the method, and results reported in an experimental study of air and water flowing in elbows and pipes.

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