Sources of vorticity are examined for a spilling breaking wave. Through the use of a honeycomb/screen section, spilling breaking waves are generated and examined. Two cases were studied. For the first case, based on the breaker height, the Reynolds and Froude numbers were 7370 and 2.04, respectively. The breaker is preceded by 1 mm wavelength capillary waves, with the largest amplitude to wavelength ratio equal to 0.18. For this case, it is found that the dominant source of vorticity flux is a viscous process, and is due to the deceleration of a thin layer of the surface fluid. Furthermore, a thin free surface fluid layer is found to precede wave breaking that moves at a faster speed with respect to the fluid directly beneath it and to the fluid bulk. For the second case, also based on the wave height, the Reynolds and Froude numbers were 1500 and 1.35, respectively. No breaking is observed for this case; rather a capillary-gravity wave is observed with 4 mm wavelength capillaries preceding the gravity wave. The largest amplitude to wavelength ratio of these capillary is 0.28. This case shows that capillary waves do not contribute to the vorticity flux, rather the only dominant source of the vorticity flux into the flow is the free surface fluid deceleration. Lastly, similar to case 1, a thin free-surface fluid layer, which moves faster than the fluid beneath it and to the fluid bulk is found preceding the capillary-gravity wave.
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