Aeration and Bubbles in the Surf Zone
5.6. Conclusions and Future Study
In this chapter, we summarize our general review of gas–water two-phase flow char-acteristics in the surf zone. There are several measurement methods for the aeration in the surf zone, such as in situ measurements, video or photographic measure-ments, laser measuremeasure-ments, and acoustic measurements. There is no one appropriate method to measure the volume of air and bubbles in the surf zone. The spatial and temporal characteristics of void fraction are summarized, and the bubble size dis-tribution is described with simple theories. Furthermore, the gas transfer prediction method is presented as a function of the bottom slope and wave characteristics for the surf zone waves.
There are many other problems such as salinity effect, scale effects, and more mathematical modeling should be investigated in the future.
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