A modification of the ITTC57 correlation line for shallow water

Abstract In ship model tests, a model-ship correlation line (e.g., the ITTC57 formula) is used to calculate the frictional resistance of both the ship and its scaled model. However, this line is designed for deep water and the effects of water depth is not considered. Research has been conducted to improve the correlation line in shallow water, but studies of the extremely shallow water case (depth/draft, h/T < 1.2) are rare. This study focuses on the friction of two ship types in extremely shallow water, where the ship’s boundary layer cannot develop freely. The physical details are analyzed based on the data generated with Computational Fluid Dynamics (CFD) calculations. The results show that for certain ship types at the same Reynolds number, the frictional resistance becomes smaller when the water is shallower. The geometry of the ship, in addition to the Reynolds number, becomes essential to the prediction of ship’s friction in extremely shallow water. Therefore, this scenario is different from intermediate shallow and deep water, and the prediction method should be considered separately. The data and analysis shown in this study can help to improve the understanding and prediction of ship’s frictional resistance in extremely shallow water.

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Nonlinear Dynamics of Rotating Shallow Water: Methods and Advances

10.1016/s1574-6909(06)x0200-9 ◽

2007 ◽

Keyword(s):

Nonlinear Dynamics ◽

Shallow Water ◽

Rotating Shallow Water

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Study of the relative sonar performance of incoherent and coherent processing against echo fading in shallow water

IEE Proceedings F Communications Radar and Signal Processing ◽

10.1049/ip-f-1.1984.0048 ◽

1984 ◽

Vol 131 (3) ◽

pp. 308 ◽

Cited By ~ 2

Author(s):

J.F. Dix ◽

R.F. Palmer

Keyword(s):

Shallow Water

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Simulation of Multilayer Shallow Water Fluid Flow Using Lattice Boltzmann Modeling and High Performance Computing

World Environmental and Water Resources Congress 2009 ◽

10.1061/41036(342)282 ◽

2009 ◽

Author(s):

K. R. Tubbs ◽

F. T. -C. Tsai

Keyword(s):

Fluid Flow ◽

Shallow Water ◽

High Performance Computing ◽

Lattice Boltzmann ◽

High Performance ◽

Lattice Boltzmann Modeling ◽

Performance Computing

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Time and Frequency Domain Analyses of Shallow Water Waves on a Slope

Coastal Engineering 1990 ◽

10.1061/9780872627765.024 ◽

1991 ◽

Author(s):

D H Swart ◽

J B Crowley

Keyword(s):

Shallow Water ◽

Frequency Domain ◽

Water Waves ◽

Shallow Water Waves

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Spatial assemblage structure of shallow-water reef fish in Southwest Australia

Marine Ecology Progress Series ◽

10.3354/meps13445 ◽

2020 ◽

Vol 649 ◽

pp. 125-140

Author(s):

DS Goldsworthy ◽

BJ Saunders ◽

JRC Parker ◽

ES Harvey

Keyword(s):

Shallow Water ◽

Reef Fish ◽

Marine Environment ◽

Fish Assemblages ◽

Canopy Cover ◽

Reef Fishes ◽

Reef Fish Assemblage ◽

Reef Type ◽

Present Distribution ◽

Southwest Australia

Bioregional categorisation of the Australian marine environment is essential to conserve and manage entire ecosystems, including the biota and associated habitats. It is important that these regions are optimally positioned to effectively plan for the protection of distinct assemblages. Recent climatic variation and changes to the marine environment in Southwest Australia (SWA) have resulted in shifts in species ranges and changes to the composition of marine assemblages. The goal of this study was to determine if the current bioregionalisation of SWA accurately represents the present distribution of shallow-water reef fishes across 2000 km of its subtropical and temperate coastline. Data was collected in 2015 using diver-operated underwater stereo-video surveys from 7 regions between Port Gregory (north of Geraldton) to the east of Esperance. This study indicated that (1) the shallow-water reef fish of SWA formed 4 distinct assemblages along the coast: one Midwestern, one Central and 2 Southern Assemblages; (2) differences between these fish assemblages were primarily driven by sea surface temperature, Ecklonia radiata cover, non-E. radiata (canopy) cover, understorey algae cover, reef type and reef height; and (3) each of the 4 assemblages were characterised by a high number of short-range Australian and Western Australian endemic species. The findings from this study suggest that 4, rather than the existing 3 bioregions would more effectively capture the shallow-water reef fish assemblage patterns, with boundaries having shifted southwards likely associated with ocean warming.

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