Koeficijent transmisije valne energije plutajućeg lukobrana pod utjecajem spektralnih valova

master's thesis

• Title (english): Wave transmission coefficient of floating breakwaters under the infulence of irregular waves
• Author: Antonija Topić
• Mentor: Damjan Bujak (mentor)
• Committee member: Goran Lončar (predsjednik povjerenstva)
• Committee member: Damir Bekić (član povjerenstva)
• Committee member: Damjan Bujak (član povjerenstva)
• Granter: University of Zagreb; Faculty of Civil Engineering; (Water Research); Zagreb
• Defense date and country: 2023-09-28, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Civil Engineering; Hydrotechnology

Abstract

Lučki akvatorij predstavlja ključnu ulogu u pomorskom prometu, upravljanju lukama i osiguranju sigurnosti plovidbe, zbog toga je bitno adekvatno zaštititi to područje. Plutajući lukobrani se često koriste kao način zaštite akvatorija i plovila u lukama, stoga je bitno ispravno procijeniti prijenos valne energije. Cilj ovog rada je ispitati ispravnost formule za procjenu koeficijenta transmisije valne energije koju je predložio Ruol, 2013. godine na plutajući lukobran π-tipa pod utjecajem spektralnih valova te analizirati utjecaj dubine vodnog stupca na koeficijent transmisije. Mjerenja su provedena u valnom kanalu na modelu plutajućeg lukobrana π-tipa izvedenog u mjerilu 1:21. Incidentni i transmitirani valni parametri mjereni su pomoću osam mjernih sondi. Na temelju mjerenih valnih serija izračunat je koeficijent transmisije. Analizom podataka uočeno je da rastom dubine vode na raste koeficijent transmisije. Pokazalo se da formula predložena od Ruol i sur, 2013. podcjenjuje mjerenja za 25% za male vrijednosti Tp/Th (1,0<Tp/Th<1,20), dok za veće omjere za velike Tp/Th (1,30<Tp/Th<1,60) i male dubine formula precjenjuje za 15% , dok je za velike dubine u tom rasponu perioda formula gotovo u potpunosti točna. Na kraju, izveden je polinom koji povezuje omjer vršnog perioda vala i prirodne oscilacije uzdizanja pontona s koeficijentom transmisije mjerenom u ovom radu.

Abstract (english)

The harbor area plays a crucial role in maritime traffic, port management, and ensuring navigational safety, making it essential to adequately protect this area. Floating breakwaters are often used as a means of protecting the harbor and vessels in ports, so it is crucial to accurately assess the transmission of wave energy. The aim of this study is to examine the accuracy of the formula for estimating the wave energy transmission coefficient proposed by Ruol et al. in 2013. for a floating breakwater of the π-type under the influence of spectral waves and to analyze the effect of water depth on the transmission coefficient. Measurements were conducted in a wave flume using a 1:21 scale model of a π-type floating breakwater. Incident and transmitted wave parameters were measured using eight measuring probes. Based on the measured wave data, the transmission coefficient was calculated. Data analysis revealed that an increase in water depth causes an increase in the transmission coefficient. It was found that the formula proposed by Ruol et al. in 2013. underestimates measurements by 25% for small values of Tp/Th (1.0<Tp/Th<1.20), while for larger Tp/Th values (1.30<Tp/Th<1.60) and shallow depths, the formula overestimates by 15%. However, for large depths within the same Tp/Th range, the formula is almost entirely accurate. Lastly, a polynomial was derived that relates the peak wave period to the natural heave oscillation of the breakwater with the transmission coefficient measured in this study.

• Keywords: plutajući lukobran; spektralni valovi; koeficijent transmisije; zaštita akvatorija; marina
• Keywords (english): floating breakwater; spectral waves; transmission coefficient; sheltering harbors; marine
• Language: croatian
• URN:NBN: urn:nbn:hr:237:668120
• Study programme: Title: Civil Engineering; specializations in: Construction Management, Transportation Engineering, Geotechnical Engineering, Hydraulic Engineering, Structural Engineering, Construction Materials, Theory and Modeling of Structures; Course: Construction Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka građevinarstva (magistar/magistra inženjer/inženjerka građevinarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2023-10-25 08:03:40