Momentum and energy exchange across an air-water interface. Partitioning (into waves and currents) and parameterization

Papadimitrakis, YA

dc.contributor.author	Papadimitrakis, YA	en
dc.date.accessioned	2014-03-01T02:43:25Z
dc.date.available	2014-03-01T02:43:25Z
dc.date.issued	2005	en
dc.identifier.issn	0967-0645	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/31399
dc.subject	Energy Flux	en
dc.subject	Wave Energy	en
dc.subject	Wind Energy	en
dc.subject.classification	Oceanography	en
dc.subject.other	Energy dissipation	en
dc.subject.other	Ocean currents	en
dc.subject.other	Water waves	en
dc.subject.other	Wind power	en
dc.subject.other	Air-water interface (AWI)	en
dc.subject.other	Energy fluxes	en
dc.subject.other	Surface drift currents	en
dc.subject.other	Wave fields	en
dc.subject.other	Oceanography	en
dc.subject.other	air-sea interaction	en
dc.subject.other	air-water interaction	en
dc.subject.other	energy flux	en
dc.subject.other	parameterization	en
dc.subject.other	Goes	en
dc.title	Momentum and energy exchange across an air-water interface. Partitioning (into waves and currents) and parameterization	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1016/j.dsr2.2005.03.006	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.dsr2.2005.03.006	en
heal.language	English	en
heal.publicationDate	2005	en
heal.abstract	Expressions have been derived to parameterize: (a) the total (time) mean wind momentum and energy fluxes across the air-sea interface, and (b) their partition into waves and a mean surface drift current, as expressed by the fractions gamma(M) and gamma(E). in terms of the wave age, c(p)/u(), and the significant slope, , of the wave field. Available laboratory and field observations support the parameterization predictions. The fraction of the wave-supported momentum, gamma(M), increases initially with the wave age (and/or the non-dimensional fetch, (x) over tilde) but, as the wave field matures, it diminishes and attains rather constant small values (of about 0.05) at large wave ages (and/or (x) over tilde). For a fixed wave-age (and/or (x) over tilde), gamma(M), increases with . The corresponding wave-supported energy fraction, gamma(E), shows a similar behavior for small and moderate wave ages (and/or (x) over tilde), although gamma(E) values remain greater than about 0.5 in the range 5 <= c(p)/u() <= 10, yet, at larger wave ages (and/or), although E values remain greater than about 0.5 in the range 5 <= c(p)/u() <= 10, yet, at larger wave ages (and/or (x) over tilde) gamma(E) appears to increase again, reaching values of about 0.8 when c(p)/u() approximate to 30, features, all in accord with experimental observations. For waves generated locally by wind, where c(p)/u() is of O(1), a significant portion of the normalized total (time) mean wind-energy flux across the interface goes directly to the surface drift current, the remaining being transferred to the waves. For mature waves or waves generated in the presence of swell, where c(p)/u() is of 0(10), this energy partition changes, the waves now supporting more energy than the surface drift current. The relative importance of the normalized wave-energy dissipation fraction, compared with the corresponding wave-energy fraction advected by the wave field and the energy fraction supported by the drift current, is also examined as the wave field develops. (c) 2005 Elsevier Ltd. All rights reserved.	en
heal.publisher	PERGAMON-ELSEVIER SCIENCE LTD	en
heal.journalName	Deep-Sea Research Part II: Topical Studies in Oceanography	en
dc.identifier.doi	10.1016/j.dsr2.2005.03.006	en
dc.identifier.isi	ISI:000230417700013	en
dc.identifier.volume	52	en
dc.identifier.issue	9-10 SPEC. ISS.	en
dc.identifier.spage	1270	en
dc.identifier.epage	1286	en