Waves Generated by Moving Vessels and Cnoidal Wave Interactions with Either a Partially-submerged Porous Barrier or a Mixed Partially-submerged and Submerged Dual Porous-Barrier System

This dissertation presents its first topic on the development of predictive models for estimating moving vessel generated maximum wave heights at Sabine–Neches Waterway in Texas. Using the recorded wave and vessels’ sailing data, the empirical approach with the calibration and validation procedures is carried out to confirm those models’ applicability. The performance of each proposed model is evaluated with two statistical measures in defining model accuracy. For coastal protection consideration, the second part of study presented focuses on the theoretical investigation of the hydrodynamic interactions between cnoidal waves and two types of porous breakwaters. One is a partially submerged porous barrier and the other one is a dual-barrier system consisting of a complete submerged frontal porous wall and a partially submerged rear porous wall. For both breakwater systems, the unknown coefficients of the velocity potentials at each flow domain are analytically derived according to the least squares method by minimizing squared error functions formulated from the mixed matching conditions. The expressions of wave elevations and hydrodynamic forces on breakwaters are also derived to calculate the reflected and transmitted waves and impact forces for breakwaters’ performance evaluations. Solution validations are performed by comparing results of limiting cases with those from other published literatures. The physical variables, such as wave height, wave length, submerged or bottom-up vertical dimensions of breakwaters, gap between two breakwaters, and porous properties, that affect wave run-up, wave reflection and transmission, and wave forces on breakwaters are investigated. For a partially submerged porous barrier case, the results show that with an increase in submerged barrier depth, the transmission coefficient decreases, although the wave force increases. Longer wave-length waves have a better tendency to be transmitted towards downstream and impact slightly greater forces on the breakwaters. However, with the inclusion of porous properties into the barrier, both the transmission coefficient and receiving wave force are considerably reduced. By considering a dual porous-barrier system, similarly, with an increase in submerged vertical dimensions of both breakwaters, the reflection coefficient is substantially decreased. Due to the blockage effect provided by the frontal barrier, the wave force on the rear barrier can be reduced when comparing to those from a single barrier case. Again, the porous effect applied to both barriers can greatly lower the values of transmission coefficient and wave forces on both breakwaters. An interesting finding for the gap effect is that the maximum wave forces on either the frontal or the rear breakwater are shown to have periodic oscillations with the peak appearing at the gap arranged to be equal to a multiple of half wave length while the minimum values of the induced maximum forces occur when the frontal and rear breakwaters are placed separately with a gap of a odd multiple of quarter wave length.

Author dc:creator

• Su, Lin 1987-

Contributors dc:contributor

• Wang, Keh-Han
• Nahas, Medhat El
• Momen, Mostafa
• Vipulanandan, Cumaraswamy
• Qian, Qin

Language dc:language

English

Handle dc:identifier.uri

https://hdl.handle.net/10657/18262

OAI identifier oai:identifier

oai:tdl-ir.tdl.org:10657/18262