scholarly journals OBSERVATION OF NEARSHORE CURRENT AND EDGE WAVES

1978 ◽  
Vol 1 (16) ◽  
pp. 45 ◽  
Author(s):  
Tamio O. Sasaki ◽  
Kiyoshi Horikawa
Keyword(s):  
Energy Spectrum ◽  
Velocity Field ◽  
Conceptual Models ◽  
Edge Waves ◽  
Nearshore Zone ◽  
Nodal Lines ◽  
Spatial Velocity ◽  
Sloping Beach

Nodal lines normal to the shoreline of infragravity low mode edge waves in the nearshore zone were observed with eleven wave staffs simultaneously with the nearshore current spatial velocity field on a gently sloping beach. About five peaks were found in the energy spectrum and their frequencies agreed well with cut-off mode edge waves [Huntley(1976)]. Based on the above observation, conceptual models of nearshore current patterns for the infragravity domain are proposed and general current patterns for the three domains are discussed by combining the horizontal patterns of Harris(1969) and the vertical patterns of Sasaki et al.(1976).

Determination of spatial velocity dispersion profile and stream velocity field in galaxy clusters - Application to Coma

1982 ◽  
Vol 252 ◽  
pp. 433 ◽  
Author(s):  
H. V. Capelato ◽  
D. Gerbal ◽  
G. Mathez ◽  
A. Mazure ◽  
E. Salvador-Sole
Keyword(s):  
Velocity Field ◽  
Galaxy Clusters ◽  
Velocity Dispersion ◽  
Stream Velocity ◽  
Dispersion Profile ◽  
Spatial Velocity

scholarly journals Fractional hyperviscosity induced growth of bottlenecks in energy spectrum of Burgers equation solutions

2019 ◽  
Vol 92 (9) ◽  
Author(s):  
Debarghya Banerjee
Keyword(s):  
Energy Spectrum ◽  
Velocity Field ◽  
Burgers Equation ◽  
Space Velocity ◽  
Real Space ◽  
Analytical Results ◽  
Turbulent Fluids ◽  
Dissipation Range

Abstract Energy spectrum of turbulent fluids exhibit a bump at an intermediate wavenumber, between the inertial and the dissipation range. This bump is called bottleneck. Such bottlenecks are also seen in the energy spectrum of the solutions of hyperviscous Burgers equation. Previous work have shown that this bump corresponds to oscillations in real space velocity field. In this paper, we present numerical and analytical results of how the bottleneck and its real space signature, the oscillations, grow as we tune the order of hyperviscosity. We look at a parameter regime α ∈ [1, 2] where α = 1 corresponds to normal viscosity and α = 2 corresponds to hyperviscosity of order 2. We show that even for the slightest fractional increment in the order of hyperviscosity (α) bottlenecks show up in the energy spectrum. Graphical abstract

Edge waves on a gently sloping beach: uniform asymptotics

1991 ◽  
Vol 233 ◽  
pp. 483-493 ◽  
Author(s):  
Peter Zhevandrov
Keyword(s):  
Finite Number ◽  
Shallow Water Equation ◽  
Uniform Asymptotics ◽  
Trapped Modes ◽  
Edge Waves ◽  
Trapped Mode ◽  
Complete Set ◽  
Constant Slope ◽  
Sloping Beach ◽  
Uniform Asymptotic Expansions

Edge waves on a beach of gentle slope ε [Lt ] 1 are considered. For constant slope, Ursell (1952) has obtained a complete set of trapped modes and shown that there exists only a finite number n of such modes, (2n + 1)β < ½π, β = tan−1ε. For non-uniform slope the formulae for the trapped-mode frequencies were heuristically derived by Shen, Meyer & Keller (1968). For small n ∼ O(1) Miles (1989) has obtained formulae which coincide with Shen et al.'s (1968) with accuracy to O(ε) and differ from them by O(ε2). However, Miles’ formulae fail at n ∼ 1/ε. In this paper it is proved that Shen et al.'s (1968) formulae are valid for all n (including n ∼ 1/ε) with accuracy to O(ε) and corrections of any order in ε are given. Uniform asymptotic expansions are obtained for the corresponding eigenfunctions. These expansions give Miles’ (1989) result for small n. The formulae for the frequencies and the eigenfunctions have the same structure for both the full dispersion system and the shallow-water equation. For small n the frequencies for both models coincide with accuracy to O(ε2), but for n ∼ 1/ε they differ by O(1). In the last section the effect of rotation following Evans (1989) is taken into account. All the asymptotics have formal character, i.e. they satisfy the corresponding equations with accuracy to O(εN), N being arbitrarily large. The rigorous justification of these asymptotics is under way.

The generation of surface waves over a sloping beach by an oscillating line source

1976 ◽  
Vol 79 (3) ◽  
pp. 573-585 ◽  
Author(s):  
Clare A. N. Morris
Keyword(s):  
Free Surface ◽  
Surface Waves ◽  
Line Source ◽  
Short Wave ◽  
Long Waves ◽  
Edge Waves ◽  
Wave Regime ◽  
Wave Solutions ◽  
Sloping Beach

AbstractA line source whose strength varies sinusoidally with time and also with the co-ordinate measured along its length is situated parallel to the shoreline of a beach of angle ¼π0. Both long-and short-wave solutions are found. It is shown that for certain positions of the source, long waves are not radiated to infinity, while in the short-wave regime, the solutions take the form of edge-waves, with resonances occurring at certain wavenumbers. Computations of the free-surface contours are presented for a range of wavenumbers.

scholarly journals Edge waves along a sloping beach

2001 ◽  
Vol 34 (45) ◽  
pp. 9723-9731 ◽  
Author(s):  
Adrian Constantin
Keyword(s):  
Edge Waves ◽  
Sloping Beach

Mechanisms for the generation of edge waves over a sloping beach

1988 ◽  
Vol 186 ◽  
pp. 379-391 ◽  
Author(s):  
D. V. Evans
Keyword(s):  
Water Wave ◽  
Wave Theory ◽  
Dominant Mode ◽  
Mode Shapes ◽  
Edge Waves ◽  
Longshore Current ◽  
Linear Water Wave Theory ◽  
Pressure Distributions ◽  
Sloping Beach ◽  
Standing Edge Waves

Two mechanisms for the generation of standing edge waves over a sloping beach are described using classical linear water-wave theory. The first is an extension of the result of Yih (1984) to a class of localized bottom protrusions on a sloping beach in the presence of a longshore current. The second is a class of longshore surface-pressure distributions over a beach. In both cases it is shown that Ursell-type standing edge-wave modes can be generated in an appropriate frame of reference. Typical curves of the mode shapes are presented and it is shown how in certain circumstances the dominant mode is not the lowest.

scholarly journals Instability of edge waves along a sloping beach

2014 ◽  
Vol 256 (12) ◽  
pp. 3999-4012 ◽  
Author(s):  
Delia Ionescu-Kruse
Keyword(s):  
Edge Waves ◽  
Sloping Beach
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