Instantaneous, full field velocity measurements have been achieved under the crest of a laboratory generated breaking wave. Measurements are made to within a few millimeters of the surface and covering an area of several hundred cm2. The generation of the waves is achieved by means of a computer controlled wave paddle and measurements are made using a full field photographic technique(PIV). The photographic records of the flow are analysed by a fully automatic rig and the measurements shown to compare well with calculated velocities from a time stepping numerical model of a similar wave.
REFERENCES
1.
Longuet-Higgins
, M.S.
and Cokelet
, E.D.
: “The Deformation of Steep Surface Waves in Water. 1. A Numerical Method of Computation
”. Proc. Royal Soc. London
, 1976
. A. 350
, 1
–26
.2.
New
, A.L.
, Mclver
, P.
and Peregrine
, D.H.
: “Computations of Overturning Waves
”, J. Fluid Mech.
, 150
. 233
–251
, 1985
.3.
Van Dorn
, W.G.
and Pazan
S.E.
: “Laboratory Investigation of Wave Breaking, Part 2, Deep Water Waves
”. Research Report, Advanced Ocean Engineering Laboratory, Scripps Inst, of Oceanography, University of California
, San Diego
, S10
Ref. No. 75-21, AOFL Report£71
, 1975
.4.
Kjelsen
, S.P.
, Vinge
, T.
and Brevig
, P.
: “Kinematics of Deep Water Breaking Waves
”, Proc. 12th Annual Offshore Technology Conference
, Texas
, 317
–325
, 1980
.5.
Easson
, W.J.
and Created
, C.A.
: “Breaking Wave Forces and Velocity Fields
”, Coastal Engineering
. 8
. 233
–41
, 1984
6.
Easson
, W.J.
: “Velocity and Force Measurements In the Splash Zone’
”, J. of Strain
, 15
–18
, Feb. 1987
.7.
Gray
, C.
, Created
, C.A.
and Fancey
, N.A.
: “The Application of PIV to Measurements Under Water Waves
”, 2nd Int. Conf. on Laser Anemometry
, Strathclyde
, 1987
.8.
Gray
, C.
and Greated
, C.A.
: “The Application of Particle Image Velocimetry to the Study of Water Waves
”, Optics and Lasers In Engineering
, 9
, 1988
.9.
Salter
, S.H.
: “Absorbing Wave Makers and Widetanks
”, Proc. Conf. Dirctional Wave Spectra Applications
, ASCE
, 1982
, 185
–200
.10.
Kjeldsen
, S.P.
: “2 and 3 Dimensional Deterministic Freak Waves
”, Norwegian Hydrodynamic Laboratories Report
, 1983
.11.
Lourenco
, L.
: “Theory and Application of Particle Image Displacement Velocimetry
”, in Lecture Series 1986-09
, Von Karman Inst. of Fluid Dynamics
, Brussels
1986
.12.
Sharpe
, J.P.
, Gray
, C.
, Greated
, C.A.
and Campbell
, M.
: “Measurement of Acoustic Streaming using PIV”, to be published, Acoustica
, 1989
.13.
McCluskey
, D.R.
, Easson
, W.J.
, Greated
, C.A.
and Glass
, D.
: “The Use of Particle Image Velocimetry to Study Roping in Pneumatic Conveyence
”, 4th European Symposium in Particle Characterisation
, Nuremberg
, W.
Germany
, Apr. 1989
.14.
Gray
, C.
and Greated
, C.A.
: “A Scanning Laser Beam System for Two Dimensional Illumination of Flow Fields
”, Lecture Series
, Von Karman Inst, of Fluid Dynamics
, Belgium
, March 1988
.15.
Sinha
, S.K.
: “Improving the Accuracy and Resolution of Particle Image or Laser Speckle Velocimetry
”. Experiments in Fluids
, 6
, 67
–68
, 1988
.16.
Burch
, J.M.
and Tokarski
, J.M.J.
: “Production of Multiple Beam Fringes from Photographic Scatterers
”, Optica Acta
, Vol 15
, No. 2
, 101
–111
, 1968
.17.
Robinson
, D.W.
: “Automatic Fringe Analysis with a Computer Image Processing System
”, Appl. Optics
, 22
, 1983
, 2169
–2176
.18.
Moraitis
, C.S.
, Buchlin
, J.M.
and Reithmuller
, M.L.
: “Improved Autocorrellation Analysis of Fringe Images for Laser Speckle Velocimetry
”, ICIASF
June 22-25, 1987
.19.
Huntley
, J.M.
: “An Image Processing System for the Anlysis of Speckle Photographs
”, J. Physics. E. Sci. Instrum.
, 19
, 1986
.20.
Bracewell
, R.N.
: “The Fourier Transform and its Applications”, McGraw-Hill
, 1986
.21.
Pickering
, C.J.D.
and Halliwell
, N.A.
: “Particle Image Velocimetry: Fringe Visibility and Pedestal Removal
”, Appl. Optics
, Vol 24
, No. 6
, 2474
–2476
, 1985
.
This content is only available via PDF.
© 1988 Laser Institute of America.
1988
Laser Institute of America
You do not currently have access to this content.