Swell and wind-waves interaction under partial reflection conditions
Metadatos
Mostrar el registro completo del ítemAutor
Addona, FabioEditorial
Universidad de Granada
Departamento
Universidad de Granada. Programa de Docotorado en Dinámica de Flujos Biogeoquímicos y sus Aplicaciones; Università degli Studi di Parma. Dottorato di Ricerca in Ingegneria Civile e ArchitetturaMateria
Flujos biogeoquímicos Viento Olas Swell Wind waves
Fecha
2021Fecha lectura
2019-03-28Referencia bibliográfica
Addona, Fabio. Swell and wind-waves interaction under partial reflection conditions. Granada: Universidad de Granada, 2021. [http://hdl.handle.net/10481/70831]
Patrocinador
Tesis Univ. Granada.Resumen
Esta investigación se refiere a un estudio experimental de la interacción
entre el viento y las olas generadas por las palas afectadas por la reflexión. El
viento y las ondas de palas regulares se generan, juntas y por separado, en un
canal de interacción océano-atmósfera, que permite la absorción activa para
obtener la reflexión deseada para cada experimento. La posibilidad de generar
una reflexión deseada en el campo de onda permite una evaluación y
cuantificación completas del efecto reflexivo en el campo de onda. En particular,
el surgimiento de tensiones adicionales, la modulación espacial del nivel medio
del agua y otros fenómenos se observan experimentalmente y se derivan
teóricamente. The main aim of this thesis is to shed light about the influence that partial
reflection (one of the most common cases encountered both in field and
laboratory studies of water waves) exerts on a wave field where regular
waves are present alone and under the action of following or opposing wind.
We have analyzed experimentally and theoretically the
ow field of paddle
waves, paddle waves plus following wind and paddle waves with opposing
wind under partial reflection conditions in laboratory, in terms of free
surface elevations, velocities and stresses.
For the theoretical and experimental analyses of the
ow field, we consider
velocities and free surface elevations as a superposition of a mean
(current), a periodic (wave) and a turbulent (fluctuating) component.
A theoretical model for the periodic (wave) component is developed by
means of a perturbation scheme considering the wave field as a superposition
of an incident, a re
ected and a bound wave. The phase shift between
the incident and the re
ected wave is included in the analysis. The theory
yields an analytical formulation of the wave components of velocities and
stresses, and a spatial variation of the mean water level. The model also
predicts the principal stresses, as well as the angle of the principal axes, of
both the Reynolds wave and turbulent stress tensors.
The wave
ume used for the experimental activity provides a complete
control of the generated and re
ected wave conditions, and is used to investigate
the influence of partial re
ection on the main variables of interest,
i.e. velocity and free surface elevation, and the combined effect of regular
waves and wind action.
We measure velocity and free surface elevation in two di erent sets
of experiments: in the rst series, paddle waves and paddle waves plus
following wind are observed and studied; in the second series, paddle waves
with opposing wind are observed and studied.
Data analysis allows a complete representation of the experimental velocities,
stresses and free surface characteristics of the
ow field. Time
average yields the mean components, phase average yields the wave (periodic)
components, while the residual part (after time and phase average)
represents the
uctuating components. A spectral filter is also used for the
separation of the free surface elevation component attributed to the paddles
(wave) and to the wind (turbulent). Several analyses of velocity and free
surface data are performed to quantify the experimental contributions of
the separated components.
The discussions of the two series of experiments show separately the
main results of the activities, and the final conclusions offer a unified vision
of the advances brought by this thesis in the wide scenario of swell and
wind waves interaction under partially-re
ective conditions.