All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 379 51 1
PDF Downloads 90 31 2

Interactions between Rain and Wind Waves

Ying-Keung PoonAir–Sea Interaction Laboratory, Graduate College of Marine Studies, University of Delaware, Lewes, Delaware

Search for other papers by Ying-Keung Poon in
Current site
Google Scholar
PubMed
Close
,
Shih TangAir–Sea Interaction Laboratory, Graduate College of Marine Studies, University of Delaware, Lewes, Delaware

Search for other papers by Shih Tang in
Current site
Google Scholar
PubMed
Close
, and
Jin WuAir–Sea Interaction Laboratory, Graduate College of Marine Studies, University of Delaware, Lewes, Delaware

Search for other papers by Jin Wu in
Current site
Google Scholar
PubMed
Close
Full access

Abstract

Effects of rain on surface waves have been investigated in a circulating wind-wave tank. Surface displacement and slope spectra under different wind velocities were measured near the upwind and downwind edges of a region with simulated rains. Spatially uniform rains of varied intensities with drop size of about 2.6 mm and spacing of 3 cm were used. Damping of surface waves by rain was observed in the frequency region of 2–5 Hz, and there was an increase in the damping rate with rain intensity. The effective eddy viscosity in the rain-induced mixed layer was found to be an order of magnitude greater than the molecular viscosity of water. As for rain-induced ripples, spectral densities of the surface slope in the frequency range of 10–100 Hz increased with the rain intensity. However, at the highest wind velocity (6.34 m s−1) of the present experiment, the ripple structure was influenced primarily by wind, with rain introducing no observable effects.

Abstract

Effects of rain on surface waves have been investigated in a circulating wind-wave tank. Surface displacement and slope spectra under different wind velocities were measured near the upwind and downwind edges of a region with simulated rains. Spatially uniform rains of varied intensities with drop size of about 2.6 mm and spacing of 3 cm were used. Damping of surface waves by rain was observed in the frequency region of 2–5 Hz, and there was an increase in the damping rate with rain intensity. The effective eddy viscosity in the rain-induced mixed layer was found to be an order of magnitude greater than the molecular viscosity of water. As for rain-induced ripples, spectral densities of the surface slope in the frequency range of 10–100 Hz increased with the rain intensity. However, at the highest wind velocity (6.34 m s−1) of the present experiment, the ripple structure was influenced primarily by wind, with rain introducing no observable effects.

Save