ShallowFlow: A Program to Model Ship Hydrodynamics in Shallow Water

Volume 1A: Offshore Technology ◽

10.1115/omae2014-23291 ◽

2014 ◽

Cited By ~ 2

Author(s):

Tim P. Gourlay

Keyword(s):

Shallow Water ◽

Cross Section ◽

Hydrodynamic Pressure ◽

Open Water ◽

Arbitrary Cross Section ◽

Far Field ◽

Shallow Water Theory ◽

Ship Hydrodynamics ◽

Cruise Ships ◽

Sinkage And Trim

In this article we present details of “ShallowFlow”, a computer program to model the hydrodynamic flow around ships in calm shallow water. The program is based on slender-body shallow-water theory. Outputs from the program include far-field hydrodynamic pressure and flow velocities; free surface drawdown; sinkage and trim. Varying transverse bathymetry including open water, dredged channels, and canals of arbitrary cross-section may be modelled. The method is best suited to displacement ships, including cargo ships, ferries, cruise ships, warships and superyachts.

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A Numerical Method for Calculation of Ship–Ship Hydrodynamics Interaction in Shallow Water Accounting for Sinkage and Trim

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4046484 ◽

2020 ◽

Vol 142 (5) ◽

Cited By ~ 1

Author(s):

Huilong Ren ◽

Chen Xu ◽

Xueqian Zhou ◽

Serge Sutulo ◽

Carlos Guedes Soares

Keyword(s):

Shallow Water ◽

Hydrodynamic Interaction ◽

Mirror Image ◽

Image Method ◽

Interaction Forces ◽

Ship Hydrodynamics ◽

Time Simulation ◽

Water Accounting ◽

Ship Hydrodynamic ◽

Sinkage And Trim

Abstract Sinkage and trim, which often occur to ships moving in shallow water, do not only have an effect on the ship–ship hydrodynamic interaction forces but also increase the risk of grounding. Potential flow-based online calculation of ship–ship hydrodynamic interaction forces without accounting for dynamic sinkage and trim is able to capture the hydrodynamic interaction effects with fair accuracy; however, there are still discrepancies in many cases, especially in the case of shallow water. An algorithm based on the potential theory has been devised for real-time simulation of the hydrodynamic interaction between two ships in shallow water accounting for sinkage and trim. The shallow water condition is modeled using the mirror image method. The sinkage and trim are solved iteratively based on the principle of hydrodynamic balance, where a mesh trimming procedure is carried out when the waterline is changed. Simulations are performed with and without accounting for the sinkage and trim, and comparison with experimental results shows a fair agreement.

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Nonlinear wave run-up in bays of arbitrary cross-section: generalization of the Carrier–Greenspan approach

Journal of Fluid Mechanics ◽

10.1017/jfm.2014.197 ◽

2014 ◽

Vol 748 ◽

pp. 416-432 ◽

Cited By ~ 35

Author(s):

Alexei Rybkin ◽

Efim Pelinovsky ◽

Ira Didenkulova

Keyword(s):

Wave Equation ◽

Shallow Water ◽

Cross Section ◽

Exact Analytical Solution ◽

Auxiliary Function ◽

Arbitrary Cross Section ◽

Channel Cross Section ◽

Linear Wave ◽

Nonlinear Shallow Water Theory ◽

Run Up

AbstractWe present an exact analytical solution of the nonlinear shallow water theory for wave run-up in inclined channels of arbitrary cross-section, which generalizes previous studies on wave run-up for a plane beach and channels of parabolic cross-section. The solution is found using a hodograph-type transform, which extends the well-known Carrier–Greenspan transform for wave run-up on a plane beach. As a result, the nonlinear shallow water equations are reduced to a single one-dimensional linear wave equation for an auxiliary function and all physical variables can be expressed in terms of this function by purely algebraic formulas. In the special case of a U-shaped channel this equation coincides with a spherically symmetric wave equation in space, whose dimension is defined by the channel cross-section and can be fractional. As an example, the run-up of a sinusoidal wave on a beach is considered for channels of several different cross-sections and the influence of the cross-section on wave run-up characteristics is studied.

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