This paper deals with the dissolved oxygen behavior on coastal areas. As water depth decreases, incoming waves are transformed and at last they become
breakers
.
Breakers
are accompanied with turbulent flow and bubbles, and so thought to have close relation to the gas absorption.
Experiments on the oxygen absorption by
breakers
were carried out and following results were obtained. The oxygen absorption in the surfzone was more efficient in plunging
breakers
than spilling
breakers
. The overall oxygen transfer coefficient
kLa (sec
-1) was directly proportional to the power of
Ho/Lo and inversely to the power of
hb/Lo. The theoretical equation to predict
kLa by the characteristics of deep water waves,
breakers
and the bed slope was derived and verified experimentally.
Using the above result and one dimensional model, the distributions of the dissolved oxygen on the shore were examined numerically. As the bed slope was small and the deep water wave height was large, the surfzone become large and the increase in the dissolved oxygen extended offshore.
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