Interfacial waves modulated by linear shear flow of the upper layer in a two-layer fluid with arbitrary layer depths

The fluid-structure energy transfer of a tensioned beam of length to diameter ratio 200, subject to vortex-induced vibrations in linear shear flow, is investigated by means of direct numerical simulation at three Reynolds numbers, from 110 to 1,100. In both the in-line and cross-flow directions, the high-wavenumber structural responses are characterized by mixed standing-traveling wave patterns. The spanwise zones where the flow provides energy to excite the structural vibrations are located mainly within the region of high current where the lock-in condition is established, i.e. where vortex shedding and cross-flow vibration frequencies coincide. However, the energy input is not uniform across the entire lock-in region. This can be related to observed changes from counterclockwise to clockwise structural orbits. The energy transfer is also impacted by the possible occurrence of multi-frequency vibrations.

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A sphere in contact with a plane wall in a slow linear shear flow

Chemical Engineering Science ◽

10.1016/0009-2509(68)89039-6 ◽

1968 ◽

Vol 23 (11) ◽

pp. 1293-1298 ◽

Cited By ~ 371

Author(s):

M.E. O'Neill

Keyword(s):

Shear Flow ◽

Plane Wall ◽

Linear Shear

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ON VORTEX LOCKING-ON PHENOMENON FOR A CABLE IN LINEAR SHEAR FLOW

Wind Engineering 1983 ◽

10.1016/b978-0-444-42341-2.50037-4 ◽

1984 ◽

pp. 289-300

Author(s):

H.G.C. Woo ◽

J.E. Cermak ◽

J.A. Peterka

Keyword(s):

Shear Flow ◽

Linear Shear

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The motion of a droplet subjected to linear shear flow including the presence of a plane wall

Journal of Fluid Mechanics ◽

10.1017/s0022112095004009 ◽

1995 ◽

Vol 302 ◽

pp. 45-63 ◽

Cited By ~ 33

Author(s):

W. S. J. Uijttewaal ◽

E. J. Nijhof

Keyword(s):

Shear Flow ◽

Flow Field ◽

Theoretical Models ◽

Boundary Integral ◽

Plane Wall ◽

Time Dependent ◽

Fluid Inertia ◽

Linear Shear ◽

Material Element ◽

Migration Velocities

A fluid droplet subjected to shear flow deforms and rotates in the flow. In the presence of a wall the droplet migrates with respect to a material element in the undisturbed flow field. Neglecting fluid inertia, the Stakes problem for the droplet is solved using a boundary integral technique. It is shown how the time-dependent deformation, orientation, circulation and droplet viscosity. The migration velocities are calculated in the directions parallel and perpendicular to the wall, and compared with theoretical models and expeeriments. The results reveal some of the shortcomings of existiong models although not all diserepancies between our calculations and known experiments could be clarified.

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Some problems concerning the production of a linear shear flow using curved wire-gauze screens

Journal of Fluid Mechanics ◽

10.1017/s0022112076000852 ◽

1976 ◽

Vol 76 (4) ◽

pp. 689-709 ◽

Cited By ~ 7

Author(s):

I. P. Castro

Keyword(s):

Shear Flow ◽

Incompressible Fluid ◽

Experimental Work ◽

Arbitrary Shape ◽

Practical Problem ◽

Analytic Solution ◽

Linear Shear ◽

Wire Gauze ◽

The Common ◽

Small Shear

The flow of an incompressible fluid through a curved wire-gauze screen of arbitrary shape is reconsidered. Some inconsistencies in previously published papers are indicated and the various approximations and linearizations (some of which are necessary for a complete analytic solution) are discussed and their inadequacies demonstrated. Attention is concentrated on the common practical problem of calculating the screen shape required to produce a linear shear flow and experimental work is presented which supports the contention that the theoretical solutions proposed by Elder (1959)–subsequently discussed by Turner (1969) and Livesey & Laws (1973)-and Lau & Baines (1968) are inadequate, although, for the case of small shear, Elder's theory appears to be satisfactory. Since, in addition, there are inevitable difficulties concerning both the value of the deflexion coefficient appropriate to any particular screen and inhomogeneities in the screen itself, it is concluded that the preparation of a curved screen to produce the commonly required moderate to large linear shear flow is bound to be somewhat empirical and should be attempted with caution.

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