A time-dependent, three-dimensional model of the Delaware Bay and River system. Part 2: Three-dimensional flow fields and residual circulation

The three dimensional model was established for studying performance of spiral groove gas face seal. According to machining features of different surface area, the seal face can be divided into three parts, rotor ring grooved area, rotor ring non-grooved area and static ring area. The effect of roughness on seal performance was analyzed based on calculation of three dimensional flow field. The analysis results show that the surface roughness of rotor ring grooved area has great influence on the seal performance, but the influence is little when roughness on non-grooved rotor ring surface and static ring surface. The influence must be considered when surface roughness of rotor ring grooved area bigger than 0.2μm. Roughness of rotor ring surface can increase the loading force while it also can cause the increase of leakage. It is important to select rational roughness when designing gas face seal.

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A Three Dimensional Model for Generating the Texture in B-Scan Ultrasound Images

Ultrasonic Imaging ◽

10.1177/016173468300500305 ◽

1983 ◽

Vol 5 (3) ◽

pp. 253-279 ◽

Cited By ~ 8

Author(s):

Mitchell M. Goodsitt ◽

Ernest L. Madsen ◽

James A. Zagzebski

Keyword(s):

Three Dimensional ◽

Time Dependent ◽

Ultrasound Images ◽

Dimensional Model ◽

Three Dimensional Model ◽

Gray Scale ◽

Receiver System ◽

Gray Scale Image ◽

Theory And Experiment ◽

Good Agreement

A three-dimensional model for production of gray scale texture in ultrasound B-mode images is described. The model computes time-dependent echo signals resulting from scattering of acoustic pulses by particles randomly distributed in an attenuating medium and transforms these signals into a gray scale image. Specific transducer and pulser-receiver characteristics are accounted for, as well as the three-dimensional nature of the problem, without loss of computational efficiency. The model generates texture that closely corresponds to that found experimentally in ultrasound images of tissue-mimicking phantoms. The dependence of the texture upon the depth of the region that was scanned and on the characteristics of the transducer-receiver system were clearly demonstrated. Good agreement between theory and experiment was found for the texture in phantoms containing simulated spherical low-scatter tumors.

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Resonance phenomena in a time-dependent, three-dimensional model of an idealized eddy

Chaos An Interdisciplinary Journal of Nonlinear Science ◽

10.1063/1.4916086 ◽

2015 ◽

Vol 25 (8) ◽

pp. 087401 ◽

Cited By ~ 13

Author(s):

I. I. Rypina ◽

L. J. Pratt ◽

P. Wang ◽

T. M. Özgökmen ◽

I. Mezic

Keyword(s):

Three Dimensional ◽

Time Dependent ◽

Dimensional Model ◽

Three Dimensional Model ◽

Resonance Phenomena

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Three-dimensional flow near a reconnection site at the dayside magnetopause: analytical solutions coupled with MHD simulations

Journal of Plasma Physics ◽

10.1017/s0022377806006325 ◽

2007 ◽

Vol 73 (6) ◽

pp. 811-819 ◽

Cited By ~ 1

Author(s):

LARS G. WESTERBERG ◽

J. VEDIN ◽

A. EKENBÄCK ◽

H. O. ÅKERSTEDT

Keyword(s):

Plasma Flow ◽

Three Dimensional ◽

Dimensional Model ◽

Three Dimensional Model ◽

Three Dimensional Flow ◽

Mhd Simulation ◽

Mhd Simulations ◽

Dayside Magnetopause ◽

Global Mhd Simulation ◽

Reconnection Site

AbstractWe present a coupling between an analytical three-dimensional model covering the plasma flow behaviour through the magnetopause transition layer near a reconnection site, with results from a global MHD simulation describing the plasma flow in the magnetosheath. The structure of the plasma flow near a reconnection site at the dayside terrestrial magnetopause is investigated, together with the development of the magnetopause transition region.

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