Wave driven devices for the oxygenation of bottom layers

Antonini, Alessandro (2014) Wave driven devices for the oxygenation of bottom layers, [Dissertation thesis], Alma Mater Studiorum Università di Bologna. Dottorato di ricerca in Ingegneria civile e ambientale, 26 Ciclo. DOI 10.6092/unibo/amsdottorato/6620.
Documenti full-text disponibili:
[img]
Anteprima
Documento PDF (English) - Richiede un lettore di PDF come Xpdf o Adobe Acrobat Reader
Download (10MB) | Anteprima

Abstract

This thesis discusses the design of a system to use wave energy to pump oxygen-rich surface water towards the bottom of the sea. A simple device, called OXYFLUX, is proposed in a scale model and tested in a wave flume in order to validate its supposed theoretical functioning. Once its effectiveness has been demonstrated, a overset mesh, CFD model has been developed and validated by means of the physical model results. Both numerical and physical results show how wave height affects the behavior of the device. Wave heights lower than about 0.5 m overtop the floater and fall into it. As the wave height increases, phase shift between water surface and vertical displacement of the device also increases its influence on the functioning mechanism. In these situations, with wave heights between 0.5 and 0.9 m, the downward flux is due to the higher head established in the water column inside the device respect to the outside wave field. Furthermore, as the wave height grows over 0.9 m, water flux inverts the direction thanks to depression caused by the wave crest pass over the floater. In this situation the wave crest goes over the float but does not go into it and it draws water from the bottom to the surface through the device pipe. By virtue of these results a new shape of the floater has been designed and tested in CFD model. Such new geometry is based on the already known Lazzari’s profile and it aims to grab as much water as possible from the wave crest during the emergence of the floater from the wave field. Results coming from the new device are compared with the first ones in order to identify differences between the two shapes and their possible areas of application.

Abstract
Tipologia del documento
Tesi di dottorato
Autore
Antonini, Alessandro
Supervisore
Dottorato di ricerca
Scuola di dottorato
Ingegneria civile ed architettura
Ciclo
26
Coordinatore
Settore disciplinare
Settore concorsuale
Parole chiave
Anoxia, wave energy, physical model, RAO, CFD, numerical wave tank
URN:NBN
DOI
10.6092/unibo/amsdottorato/6620
Data di discussione
19 Maggio 2014
URI

Altri metadati

Statistica sui download

Gestione del documento: Visualizza la tesi

^