Edge waves

Zhang Hadan and Tutor Yin Chongfu, The through wave and edge wave radiated in solid medium by the energy exchanger of round thickness modes ", The Acoustics Institute of Chinese Academy of Sciences 1984. 

Now in (20) one could recognize Eq. (9) by replacing W with and P(E - H) x with xT> which is indeed an edge wave function even if x is not. To make sure that the operator W projects onto the complete space of i /s the rank of P which yields the rank of W must be at least N . 

When the coil being processed has excessive edge wave, or loose edges, strand length differential can be present becau.se the sine-wave edge length is... 

Edge-to-edge fiber length differential such as edge wave, quarter buckle, center buckle, camber, and twist. ... 

Twist is a fairly common problem, but somewhat more difficult to categorize (Fig. 7). It is, in fact, geometrically related to edge wave. If the material... 

If overloaded, the pinch rolls especially, and also the work rolls, will deflect outward in the center (Fig. 16), putting excessive pressure on the edges of the material, easily introducing undesired edge wave into the flat-metal product. 

Figure 21 Leveler setting for elimination of edge wave.

In the case of extreme twist, one would have to alter the backup setting to elongate the shorter portions of the material relative to the longer portions, similar to the issue with edge wave. With twist, it will be necessary to identify the location of the center of the helix in order to know which portion should be elongated. 

Figure 5 Controlled edge wave can be induced by a precision roller leveler.

We emphasize that these surface waves are unique for finite arrays. They will not appear on an infinite array and will consequently not be printed out by, for example, the PMM program that deals strictly with infinite arrays. Nor should they be confused with what is sometimes referred to as edge waves [28], The propagation constant of these equals that of free space, and they die out as you move away from the edges. See also Section 1.5.3. 

Should the Surface Waves Encountered Here Be Called Edge Waves ... 

It has been suggested to denote the surface waves introduced in this chapter as edge waves for no reason other than they originate at the edges of the array. This confronts us with certain problems. 

First of all, the term edge wave has been used to denote a wave that propagates along and not orthogonal to an edge [30], In other words, we are talking about two entirely different kinds of waves. 

T. Nguyen and A. Dominek, An Edge Wave Reflection Coefficient, Technical Report 721929-22, The Ohio State University Electroscience Laboratory, March 1990. 

Greenspan resonance when Ui = Cj, the alongshore component Ui) of the atmospheric disturbance velocity equals the phase speed of the jth mode of edge waves (cj) ... 

H. P. Greenspan, The generation of edge waves by moving pressure disturbances, J. Fluid Mech. 1, 574-592 (1956). 

J. Oltman-Shay and R. T. Guza, Infragravity edge wave observations on two California beaches, J. Phys. Oceanor. 17, 644-663 (1987). 

Fig. 39.11. Circular island in DSWG basin with trapped edge wave wrapping around lee side. " ...

Interference in the center of the far field is always constructive if the edge waves are within half the wavelength A./2 of the plane wave. This eriterion can be used to pre-diet the range of the near field, L, using simple geometry. If the aperture of the transducer is D then... 

At the side of the beam in the far field, the edge waves from opposite sides of the aperture interfere destructively creating an amplitude null, or node, in the shape of a cone of semi-angle i>. Outside this cone the interference is successively constmctive and destractive. Simple geometry can be used to estimate... 

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