LEADER 03538nam 2200337 450 001 9910688493703321 005 20230703192224.0 035 $a(CKB)5400000000043199 035 $a(NjHacI)995400000000043199 035 $a(EXLCZ)995400000000043199 100 $a20230703d2005 uy 0 101 0 $aeng 135 $aur||||||||||| 181 $ctxt$2rdacontent 182 $cc$2rdamedia 183 $acr$2rdacarrier 200 10$aGas transfer at the air-water interface in a turbulent flow environment /$fGerhard H. Jirka 210 1$aKarlsruhe :$cKIT Scientific Publishing,$d2005. 215 $a1 online resource (ix, 128 pages) 311 $a1000003544 330 $aThe gas transfer process across the air-water interface in a ottom-shear-induced turbulent environment was investigated to gain improved fundamental understanding of the physical mechanisms that control the process. For this purpose, it is necessary to reveal the hydrodynamics of the flow field as well as the molecular diffusion and the turbulent transport contributions to the total flux. Therefore, detailed laboratory experiments were conducted to obtain these information.The experiments were performed in a grid-stirred tank using a combined Particle Image Velocimetry - Laser Induced Fluorescence (PIV-LIF) technique that has been developed for these near surface gas transfer measurements. The turbulence characteristics of the velocity near the interface were acquired from the PIV measurements and showed generally good agreement with the theoretical profiles from Hunt & Graham (1978). The LIF technique enabled visualization of the planar concentration fields which provided more insight into the gas transfer mechanisms. The high data resolution allowed detailed quantification of the concentration distribution within the thin aqueous boundary layer. The mean and turbulent fluctuation characteristics of the concentration could be elucidated and the molecular diffusion contribution to the total flux across the interface could be determined. With the combined PIV-LIF technique, which enables simultaneous and spatially synoptic measurements of 2D velocity and concentration fields, the turbulent mass flux term cw and also the total mass flux across the air-water interface could be quantified directly. For the first time, a particular trend can be inferred from the measured mean cw profiles. It could also be shown that the contribution of the turbulent mass flux to the total gas flux is significant. The co-spectra indicated different behavior for the cases with lower and higher turbulent Reynolds numbers.The interrelated interpretation of the obtained results suggest that the gas transfer process is controlled by a spectrum of different eddy sizes and the gas transfer at different turbulence levels can be associated to certain eddy sizes. For high turbulence levels the gas transfer should be asymptotic to the small eddy model, whereas for low turbulence level to the large eddy model. The new results of turbulent mass flux should aid as an excellent database in refining numerical models and developing more accurate models for the prediction of the transfer velocity. 606 $aParticle image velocimetry 615 0$aParticle image velocimetry. 676 $a620.1 700 $aJirka$b Gerhard H.$0632646 801 0$bNjHacI 801 1$bNjHacl 906 $aBOOK 912 $a9910688493703321 996 $aGas transfer at the air-water interface in a turbulent flow environment$93395446 997 $aUNINA LEADER 01775nam 2200613 450 001 9910822881203321 005 20230617013256.0 010 $a1-78673-448-6 010 $a1-78672-448-0 035 $a(CKB)4340000000262153 035 $a(MiAaPQ)EBC5331476 035 $a(Au-PeEL)EBL5331476 035 $a(CaPaEBR)ebr11535206 035 $a(OCoLC)1030822610 035 $a(EXLCZ)994340000000262153 100 $a20180427d2004 uy 0 101 0 $aeng 135 $aurcnu|||||||| 181 $ctxt$2rdacontent 182 $cc$2rdamedia 183 $acr$2rdacarrier 200 10$aUnderstanding urban tourism $eimage, culture and experience /$fMartin Selby 210 1$aLondon ;$aNew York :$cI.B. Tauris,$d2004. 215 $a1 online resource (xii, 228 pages) $cillustrations 225 1 $aTourism, retailing and consumption series 311 $a1-86064-801-0 311 $a1-86064-800-2 320 $aIncludes bibliographical references and index. 410 0$aTourism, retailing and consumption. 606 $aTourism 606 $aCities and towns 606 $aUrban economics 606 $aTourisme urbain 606 $aToeristenindustrie$2gtt 606 $aSteden$2gtt 606 $aMarketing$2gtt 606 $aPlanning$2gtt 615 0$aTourism. 615 0$aCities and towns. 615 0$aUrban economics. 615 6$aTourisme urbain. 615 17$aToeristenindustrie. 615 17$aSteden. 615 17$aMarketing. 615 17$aPlanning. 676 $a338.4791091732 700 $aSelby$b Martin$f1970-$01720842 801 0$bMiAaPQ 801 1$bMiAaPQ 801 2$bMiAaPQ 906 $aBOOK 912 $a9910822881203321 996 $aUnderstanding urban tourism$94119891 997 $aUNINA