TITLE:
Wind Wave Growth
AUTHORS:
Kern E. Kenyon
KEYWORDS:
Wind Wave Growth, Compressed Air Boundary Layer
JOURNAL NAME:
Natural Science,
Vol.13 No.5,
May
10,
2021
ABSTRACT: A
recent formula for the lift force on a low speed wing of circular arc
cross-section [1] is
adapted to the upward pressure force on the crests of a surface gravity wave
propagating in the wind. In both cases, the main
feature is the utilization of the air’s compressibility. At and near a wave
crest, it
is predicted that the air density is increased over the ambient value and that
the air density decreases inversely as the square of the upward distance from
the radius of curvature of the crest. As a consequence, the air
pressure also decreases upward inversely as the square of the same distance.
Therefore, an upward pressure force on each crest occurs which presumably will
make the crests grow. Growth rates are largest for small wavelengths and large mean slopes of the wave
surface. Contrary winds should produce wave growth (not damping) as well
as no wind at all.