Computational fluid dynamics analysis of cylindrical floating breakwater towards reduction of sediment transport

A. Fitriadhy; M.A. Faiz; S.F. Abdullah

doi:10.15282/jmes.11.4.2017.10.0276

Authors

A. Fitriadhy Program of Maritime Technology, School of Ocean Engineering, Universiti Malaysia Terengganu, Malaysia.
M.A. Faiz Program of Maritime Technology, School of Ocean Engineering, Universiti Malaysia Terengganu, Malaysia.
S.F. Abdullah Program of Maritime Technology, School of Ocean Engineering, Universiti Malaysia Terengganu, Malaysia.

DOI:

https://doi.org/10.15282/jmes.11.4.2017.10.0276

Keywords:

Coastal protection; cylindrical floating breakwater; sediment transport; computational fluid dynamics.

Abstract

Floating breakwater becomes an alternative and reliable coastal area protection as it is cheaper in production cost as compared to conventional bottom-fixed breakwater. Floating breakwater system would be the best decision in order to control sedimentation that threatens the shore due to erosion. This study proposes to analyse Cylindrical Floating Breakwater (CFB) aimed at gaining a sufficient reduction in the sediment transport rate along the shore (case study at Tok Jembal Beach in Kuala Terengganu) by using CFD approach. Several parameters for the effects of wavelengths and vertical clearance between the CFB and seabed on the gradient of suspended and packed sediment were simulated by using Flow3D. A wave boundary was assigned to give an insight on regular waves effects to the parameters used in the simulation. The results showed that the presence of CFB markedly reduced the concentration and mass of suspended sand, gravel and coarse gravel for the whole range of wavelengths considered. Besides, it was found that varying the relative clearance of the floating breakwater and seabed was particularly sensitive to the concentration and mass of suspended sediment. Meanwhile, the bulk of sediment mass and concentration remain insignificant for the investigated wavelength and vertical clearance. From this standpoint, the cylindrical floating breakwater (CFB) could significantly minimise the gradient of sediment transport along the breakwater-beach distance while its installation depth may be optimised for circumstances to save cost, avoid breaking waves and morphological changes, ship traffic routes and etc.

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