Air-sea momentum transfer in high wind conditions: laboratory experiments.

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Air-sea momentum transfer in high wind
conditions laboratory experiments.
Ivan Savelyev
Sponsored by
Advisors Brian Haus and Mark Donelan
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Background
Early theoretical works
Jeffreys, H., 1924 Miles, J. W., 1957 Airflow separation, sheltering hypothesis. Analytical solution for wind-wave generation.
Experimental efforts
Snyder et al. 1981, Hsiao et al. 1983, Donelan 1999, Donelan et al. 2006, Laboratory and field observations of wave induced static pressure fluctuations.
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Experiment Setup
Air-Sea Interactions Salt-Water Tank at RSMAS,
University of Miami. Dimensions 15x1x1
meters, Maximum wind speed U30 m/s, Fully
programmable wave-maker with wave height up to H
10 cm.
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Wave-follower experimental setup.
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Wave-follower in motion
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Digital Laser Elevation Gauge (DLEG)
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DLEG image of the air-sea interface at
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Figure 2 from On the limiting aerodynamic
roughness of the ocean in very strong winds,
Donelan et al., 2004.
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Summary and future work
1) The new high precision wave-follower system
was developed and proofed to be successful. 2)
First wave-follower based static pressure
measurements show that wave growth function
keeps growing quadratically as wind forcing
enters hurricane-like conditions. 3) Both
dimensional and non-dimensional approaches are
necessary to resolve form drag contribution to a
total drag in high-wind conditions. 4) In the
future experiments will be studied as a
function of wind speed, wind forcing and wave
steepness.