The two-dimensional flow oscillations of a fluid in a spindle-shaped basin; application to Port Kembla Outer Harbour, N. S. W., Australia

1972 ◽  
Vol 23 (1) ◽  
pp. 1 ◽  
Author(s):  
DJ Clarke ◽  
ND Thomas
Keyword(s):  
Amplification Factor ◽  
Resonant Mode ◽  
Two Dimensional ◽  
Storm Activity ◽  
Long Wave ◽  
Model Study ◽  
Study Results ◽  
Two Dimensional Flow ◽  
History Of ◽  
Flow Oscillations

Port Kembla Outer Harbour has a history of severe ranging during storm activity, and hence a knowledge of its resonant behaviour is a necessary requirement towards understanding the cause of the range action. The Harbour has been shown to be suitably approximated by a spindle shape, which is the name given by Hidaka (1931) to a basin whose surface perimeter is defined as the intersection of two confocal parabolae. In this paper Hidaka's results are enlarged, more basic harmonics being found. These are then applied to the Outer Harbour which is assumed to be excited by a fully formed clapotis with an antinode at the entrance. The two particular harmonics which are most likely to be excited are found to have the same period of 153 sec. Experimental evidence has given long wave periods in the Harbour as 150 and 160 sec. The resonant mode corresponding to a period of 54 sec is found to have a large amplification factor at the entrance to the Inner Harbour, and this may be compared with model study results where at 56-58 sec the range action is greatest.

On resonance of an offshore channel bounded by a reef

1981 ◽  
Vol 32 (6) ◽  
pp. 833 ◽  
Author(s):  
VT Buchwald ◽  
JW Miles
Keyword(s):  
Wave Equations ◽  
Amplification Factor ◽  
Dominant Mode ◽  
Two Dimensional ◽  
Barrier Reef ◽  
Reef Lagoon ◽  
Long Wave ◽  
Frictional Damping ◽  
Linear Friction ◽  
Western Australian

The period and amplification factor for the dominant mode in a channel formed by the shore and a submerged parallel reef (which separates the channel from deeper water) are calculated from the two- dimensional long-wave equations with linear friction. Results are obtained for both narrow and wide reefs and are compared with observed oscillations on the Western Australian coast and on the Barrier Reef. Although the calculated periods might explain the anomalous tides in the Barrier Reef lagoon. it seems that there is sufficient frictional damping to prevent the required amplification.

Incremental constitutive relations for granular materials based on micromechanics

1993 ◽  
Vol 441 (1913) ◽  
pp. 433-463 ◽  
Keyword(s):  
Granular Materials ◽  
Constitutive Equations ◽  
Constitutive Relations ◽  
Rate Of Change ◽  
Contact Forces ◽  
Two Dimensional ◽  
Microstructural Parameters ◽  
Two Dimensional Flow ◽  
History Of ◽  
Shearing Deformation

Micromechanically based constitutive relations for two-dimensional flow of granular materials are presented. First, overall stresses are related to the interparticle forces and microstructural parameters. Then, the overall velocity gradient is related to measures of relative sliding and rotation of granules. The notion of the class of granules with continuously evolving distribution of contact normals, is introduced. Simple local constitutive relations are considered for the rate of change of the contact forces, the evolution of the contact normals, the mechanism of local failure, and the density of contacts in a particular class. This leads to macroscopic rate constitutive equations through a Taylor averaging method. Due to nonlinearity of the rate constitutive equations, the response is computed by an incremental procedure. As an illustration, the overall response of a two-dimensional assembly of discs subjected to an overall shearing deformation is determined. In addition, explicit results are presented for the evolution of fabric, contact forces, and the history of active and inactive classes of contacts. The stress-strain relations and the evolution of fabric and contact forces are in qualitative agreement with the observed behaviour of granular materials. In light of these results, the mechanisms of failure and inelastic deformation of dense as well as loose granular materials are discussed.

Two-Dimensional Flow of Polymer Solutions Through Porous Media

1999 ◽  
Vol 2 (3) ◽  
pp. 251-262
Author(s):  
P. Gestoso ◽  
A. J. Muller ◽  
A. E. Saez
Keyword(s):  
Porous Media ◽  
Polymer Solutions ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Two Dimensional Flow

Efficacy of intrauterine administration of autologous peripheral blood mononuclear cells prior to embryo transfer in patients with recurrent implantation failures in assisted reproductive technology programmes

GYNECOLOGY ◽  
2018 ◽  
Vol 20 (2) ◽  
pp. 28-33
Author(s):  
T S Amyan ◽  
S G Perminova ◽  
L V Krechetova ◽  
V V Vtorushina
Keyword(s):  
Embryo Transfer ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Peripheral Blood Mononuclear ◽  
Study Objective ◽  
Study Results ◽  
Blood Mononuclear Cells ◽  
History Of ◽  
Group 2

Study objective. To evaluate the efficacy of intrauterine administration of autologous peripheral blood mononuclear cells (PBMC) prior to embryo transfer in patients with recurrent implantation failures in IVF program. Materials and methods. The study enrolled 129 patients with recurrent implantation failures in an IVF programme. Group 1 - 42 patients who had intrauterine administration of autologous PBMC activated with hCG (Pregnyl 500 IU). Group 2 - 42 patients who had intrauterine administration of autologous PBMC without hCG activation. Group 3 (placebo) - 45 patients who had intrauterine administration of saline. Study results. In the hCG-activated PBMC group, the rates of positive blood hCG tests, implantation, and clinical pregnancy were significantly higher than the respective rates in the non-activated PBMC group and in the placebo group, both in a stimulated cycle and in an FET cycle (р≤0.05). Conclusion. Intrauterine administration of autologous PBMC prior to embryo transfer in an IVF/ICSI programme increases the efficacy of IVF program in patients with a history of recurrent implantation failures.

STUDY OF NON-ISOTHERMAL TWO-DIMENSIONAL FLOW OVER A SQUARE CYLINDER IMMERSED IN A CHANNEL

2019 ◽  
Author(s):  
Gabriel Machado dos Santos ◽  
Ítalo Augusto Magalhães de Ávila ◽  
Hélio Ribeiro Neto ◽  
João Marcelo Vedovoto
Keyword(s):  
Two Dimensional ◽  
Square Cylinder ◽  
Dimensional Flow ◽  
Two Dimensional Flow

scholarly journals Two-Dimensional Numerical Modeling of Flow in Physical Models of Rock Vane and Bendway Weir Configurations

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 458
Author(s):  
Drew C. Baird ◽  
Benjamin Abban ◽  
S. Michael Scurlock ◽  
Steven B. Abt ◽  
Christopher I. Thornton
Keyword(s):  
Numerical Modeling ◽  
Physical Model ◽  
Numerical Models ◽  
Hydraulic Performance ◽  
Physical Models ◽  
Protection Measures ◽  
Design Engineers ◽  
Model Study ◽  
Study Results ◽  
Wide Range

While there are a wide range of design recommendations for using rock vanes and bendway weirs as streambank protection measures, no comprehensive, standard approach is currently available for design engineers to evaluate their hydraulic performance before construction. This study investigates using 2D numerical modeling as an option for predicting the hydraulic performance of rock vane and bendway weir structure designs for streambank protection. We used the Sedimentation and River Hydraulics (SRH)-2D depth-averaged numerical model to simulate flows around rock vane and bendway weir installations that were previously examined as part of a physical model study and that had water surface elevation and velocity observations. Overall, SRH-2D predicted the same general flow patterns as the physical model, but over- and underpredicted the flow velocity in some areas. These over- and underpredictions could be primarily attributed to the assumption of negligible vertical velocities. Nonetheless, the point differences between the predicted and observed velocities generally ranged from 15 to 25%, with some exceptions. The results showed that 2D numerical models could provide adequate insight into the hydraulic performance of rock vanes and bendway weirs. Accordingly, design guidance and implications of the study results are presented for design engineers.

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