Vortical structure evolutions and spreading characteristics of a plane jet flow under anti-symmetric long-wave excitation

2009 ◽  
Vol 33 (4) ◽  
pp. 630-641 ◽  
Author(s):  
Yung-Lan Yeh ◽  
Cheng-Chiang Hsu ◽  
Chih-Huang Chiang ◽  
Fei-Bin Hsiao
Keyword(s):  
Vortical Structure ◽  
Jet Flow ◽  
Wave Excitation ◽  
Long Wave ◽  
Plane Jet

scholarly journals Image Measurement of Plane Jet Flow with Self-Induced Sloshing

1999 ◽  
Vol 19 (Supplement1) ◽  
pp. 297-300
Author(s):  
Taketoshi OKUNO ◽  
Shigeru NISHIO ◽  
Hidenaga IWAHASHI
Keyword(s):  
Jet Flow ◽  
Image Measurement ◽  
Plane Jet

scholarly journals Hydroelastic analysis of ice shelves under long wave excitation

2015 ◽  
Vol 3 (5) ◽  
pp. 3057-3075 ◽  
Author(s):  
T. K. Papathanasiou ◽  
A. E. Karperaki ◽  
E. E. Theotokoglou ◽  
K. A. Belibassakis
Keyword(s):  
Finite Element ◽  
Extreme Values ◽  
Tsunami Wave ◽  
Wave Length ◽  
Bending Moment ◽  
Stable Configuration ◽  
Wave Excitation ◽  
Ice Shelf ◽  
Long Wave ◽  
Hydroelastic Analysis

Abstract. The transient hydroelastic response of an ice shelf under long wave excitation is analysed by means of the finite element method. The simple model, presented in this work, is used for the simulation of the generated kinematic and stress fields in an ice shelf, when the latter interacts with a tsunami wave. The ice shelf, being of large length compared to its thickness, is modelled as an elastic Euler–Bernoulli beam, constrained at the grounding line. The hydrodynamic field is represented by the linearised shallow water equations. The numerical solution is based on the development of a special hydroelastic finite element for the system of governing of equations. Motivated by the 2011 Sulzberger Ice Shelf (SIS) calving event and its correlation with the Honshu Tsunami, the SIS stable configuration is studied. The extreme values of the bending moment distribution in both space and time are examined. Finally, the location of these extrema is investigated for different values of ice shelf thickness and tsunami wave length.

The Shear Layers of a Two-Dimensional Jet Excited by Flexible Wires

2003 ◽  
Vol 125 (3) ◽  
pp. 597-599
Author(s):  
Ming-huei Yu ◽  
Yi-chun Liao ◽  
Chung-ho Tseng
Keyword(s):  
Spectral Analysis ◽  
Shear Layer ◽  
Density Ratio ◽  
Jet Flow ◽  
Shear Layers ◽  
Spanwise Direction ◽  
External Forcing ◽  
Two Dimensional ◽  
Air Jet ◽  
Plane Jet

A two-dimensional air jet, heated at a density ratio of 0.8, under external forcing by flexible wires is investigated experimentally. In each shear layer of the hot jet flow, a wire of diameter 0.23 mm (0.015 jet width) is flexibly mounted along the spanwise direction. By flow visualization, temperature measurements, and spectral analysis, the study demonstrates that the wires have quite different effects on the jet flow depending on that the wires are motionless or vibrating in the flow, and the shear layers of the heated plane jet can be manipulated by means of flexible wires.

scholarly journals Hydroelastic analysis of ice shelves under long wave excitation

2015 ◽  
Vol 15 (8) ◽  
pp. 1851-1857 ◽  
Author(s):  
T. K. Papathanasiou ◽  
A. E. Karperaki ◽  
E. E. Theotokoglou ◽  
K. A. Belibassakis
Keyword(s):  
Finite Element ◽  
Extreme Values ◽  
Tsunami Wave ◽  
Wave Length ◽  
Bending Moment ◽  
Stable Configuration ◽  
Wave Excitation ◽  
Ice Shelf ◽  
Long Wave ◽  
Hydroelastic Analysis

Abstract. The transient hydroelastic response of an ice shelf under long wave excitation is analysed by means of the finite element method. The simple model, presented in this work, is used for the simulation of the generated kinematic and stress fields in an ice shelf, when the latter interacts with a tsunami wave. The ice shelf, being of large length compared to its thickness, is modelled as an elastic Euler-Bernoulli beam, constrained at the grounding line. The hydrodynamic field is represented by the linearised shallow water equations. The numerical solution is based on the development of a special hydroelastic finite element for the system of governing of equations. Motivated by the 2011 Sulzberger Ice Shelf (SIS) calving event and its correlation with the Honshu Tsunami, the SIS stable configuration is studied. The extreme values of the bending moment distribution in both space and time are examined. Finally, the location of these extrema is investigated for different values of ice shelf thickness and tsunami wave length.

Fluorescence properties of some isoquinoline alkaloids

1985 ◽  
Vol 50 (6) ◽  
pp. 1312-1328 ◽  
Author(s):  
Jan Kovář ◽  
Karel Šimek ◽  
Eva Kožoušková ◽  
Hana Klukanová ◽  
Jiří Slavík
Keyword(s):  
Excited States ◽  
Fluorescence Properties ◽  
Hydroxyl Groups ◽  
Wave Excitation ◽  
Isoquinoline Alkaloids ◽  
Polar Medium ◽  
Excitation Peak ◽  
Protoberberine Alkaloids ◽  
Long Wave ◽  
Effect Of Polarity

The fluorescence properties of 28 isoquinoline alkaloids have been investigated. In most of them the chromophore responsible for fluorescence was the benzene ring with electron-donor substituents containing oxygen. The long-wave excitation peak practically coincides with the long-wave absorption peak of these substances, covering the region from 284 to 293 nm, the maximum emission being in the range 320-332 nm. With alkaloids having a number of conjugated rings, both excitation and emission were observed at higher wavelengths. Only protoberberine alkaloids behaved as hydrophobic probes, i.e. transfer of these compounds into a less polar medium produced a marked hypsochromic shift and a higher intensity of emission. The effect of polarity on the behaviour of tetrahydroprotoberberines, protopines, pavinanes, aporphines and benzophenanthridines was not so pronounced. Changes of pH manifested themselves most markedly in compounds with dissociable hydroxyl groups; the majority of phenolates did not fluoresce.The phenol group pK values of these compounds in the excited state were lower than in the ground state (which ranged between 8.4 and 10.4). The relations between the apparent pK, determined from fluorescence data, and the pK's of these compounds in the ground and the excited states are discussed.

Fluorometric continuous kinetic assay of α-chymotrypsin using new protease substrates possessing long-wave excitation and emission maxima

1988 ◽  
Vol 171 (2) ◽  
pp. 393-397 ◽  
Author(s):  
John H. Baustert ◽  
Otto S. Wolfbeis ◽  
Robert Moser ◽  
Ernst Koller
Keyword(s):  
Wave Excitation ◽  
Kinetic Assay ◽  
Long Wave

A note on the conservation of the axial momentum of a turbulent jet

1978 ◽  
Vol 87 (1) ◽  
pp. 55-63 ◽  
Author(s):  
Nikolas E. Kotsovinos
Keyword(s):  
Conservation Law ◽  
Momentum Flux ◽  
Pressure Field ◽  
Jet Flow ◽  
Experimental Results ◽  
Turbulent Jet ◽  
Ambient Fluid ◽  
Induced Flow ◽  
Plane Jet ◽  
Direction Opposite

The conservation law for the flux of axial momentum in a turbulent jet is examined. The examination discloses that for a plane jet out of a wall the momentum flux is reduced appreciably because the induced flow towards the jet has a component in the direction opposite to the main jet flow and because of the pressure field generated in the ambient fluid. Existing experimental results confirm this conclusion.

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