Study of Undertow for Different Beach Profile

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Study of Undertow for Different Beach
Profile   Undertow, average velocity over one
wave period, is dominating in the velocity field
in surf zone. It is essential in order to
estimate sediment transport as well as beach
topography. The objective of the study is to
investigate interaction between cross-shore beach
profile and undertow in surf zone. In surf zone
velocity field consists of steady current,
irrotational wave motion, rotational wave motion
and turbulence. Laboratory measurement in surf
zone is complicated to distinguish components of
velocity field. Laser Doppler Velocimeter(LDV),
Acoustic Doppler Velocimeter(ADV) etc, are used
to record velocity data, but are not efficient
after breaking because of bubbles in vortex.
Vortex size and velocity of particles in vortex
are essential to understand velocity filed. One
way is to trace the movement and estimate the
density of bubbles in order to quantify vortex
size and velocity of bubbles in vortex.
Figure Vortex size is estimated in surf zone
captured by High Speed Camera