MATHEMATICAL METHODS FOR CALCULATING SHIP HULL FORMS OF DECREASED WAVE-MAKING RESISTANCE

Ship Hull Form Optimization Using Artificial Bee Colony Algorithm

10.5957/smc-2014-t47 ◽

2014 ◽

Author(s):

Fuxin Huang ◽

Lijue Wang ◽

Chi Yang

Keyword(s):

Drag Reduction ◽

Artificial Bee Colony ◽

Interpolation Method ◽

Ship Hull ◽

Mathematical Functions ◽

Hull Form ◽

Abc Algorithm ◽

Bee Colony ◽

Hull Forms ◽

Fast Flow

In this paper, artificial bee colony (ABC) algorithms are introduced to optimize ship hull forms for reduced drag. Two versions of ABC algorithm are used: one is the basic ABC algorithm, and the other is an improved artificial bee colony (IABC) algorithm. A recently developed fast flow solver based on the Neumann-Michell theory is used to evaluate the drag of the ship in the optimization process. The ship hull surface is represented by discrete triangular panels and modified using radial basis function interpolation method. The developed optimization algorithms are first validated by benchmark mathematical functions with different dimensions. They are then applied to the optimization of DTMB Model 5415 for reduced drag. Two optimal hull forms are obtained by the ABC and the IABC algorithms. A large drag reduction is obtained by both of the algorithms. The optimal hull form obtained by the IABC algorithm has larger drag reduction than that of the hull form from the ABC algorithm. The results show that two ABC algorithms can be used for optimizing ship hull forms and the IABC algorithm has better performance than the ABC algorithm for the tested case in ship hull form optimization.

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A Comparison of Several Strategies to Optimize a Ship’s Aft Body

Journal of Ship Production and Design ◽

10.5957/jspd.2011.27.4.202 ◽

2011 ◽

Vol 27 (04) ◽

pp. 202-211

Author(s):

Auke van der Ploeg

Keyword(s):

Viscous Flow ◽

Scale Effects ◽

Full Scale ◽

Ship Hull ◽

Hull Form ◽

Wake Field ◽

Hull Forms ◽

Definition Of

This paper describes a procedure to optimize ship hull forms, based on double body viscous flow computations with PARNASSOS. A flexible and effective definition of parametric hull form variations is used, based on interpolation between basis hull forms. One of the object functions is an estimate of the required power. In this paper we will focus on how to improve this estimate, by using the B-series of propellers. Results of systematic variations applied to the VIRTUE tanker together with scale effects in the computed trends will be discussed. In addition, we will demonstrate how the techniques discussed in this paper can be used to design a model that has a wake field that strongly resembles the wake of a given containership ship at full scale.

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An optimization approach for fairing of ship hull forms

Ocean Engineering ◽

10.1016/j.oceaneng.2005.11.014 ◽

2006 ◽

Vol 33 (16) ◽

pp. 2105-2118 ◽

Cited By ~ 21

Author(s):

Ebru Sariöz

Keyword(s):

Ship Hull ◽

Optimization Approach ◽

Hull Forms

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Geometrical Variation and Distortion of Ship Hull Forms

Marine Technology and SNAME News ◽

10.5957/mt1.2003.40.4.239 ◽

2003 ◽

Vol 40 (04) ◽

pp. 239-248

Author(s):

Ebru Narh ◽

Kadir Sariöz

Keyword(s):

Computer Aided Design ◽

Ship Hull ◽

Hydrodynamic Performance ◽

Hull Form ◽

Nonlinear Distortions ◽

Form Design ◽

Hull Form Design ◽

Geometrical Variation ◽

Hull Forms ◽

Aided Design

Because of the risk involved with starting the hull form design from scratch, the designer most frequently initiates the hull form design process with a parent form that has satisfactory hydrodynamic performance. Hence, linear and nonlinear variation and distortion techniques have found wide applications in the hull form design studies. Some of these methods are simple and easy to apply by practicing naval architects, whereas others may be considered too complicated and difficult to use without simplifications. Existing and emerging techniques to distort a parent ship hull form are discussed and applied to a typical ship form. These techniques range from a simple one minus prismatic method to complex nonlinear distortions and include emerging computer-aided design (CAD) methods, such as shape averaging. The applications indicate that the techniques presented can be safely applied to conventional ship hull forms. The advantages and drawbacks of these methods are discussed, and numerical results are presented.

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Computer-aided Fairing and Direct Numerically Controlled Machining of Ship Hull Hydrodynamic Testing Models

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-1988-0007 ◽

1988 ◽

Vol 12 (1) ◽

pp. 43-48 ◽

Cited By ~ 1

Author(s):

S. Bedi ◽

W. Chernoff ◽

G.W. Vickers

Keyword(s):

End Milling ◽

Three Dimensional ◽

Ship Hull ◽

Cnc Machine ◽

Computer Aided ◽

Original Table ◽

Minimum Number ◽

Hull Forms ◽

And Control ◽

Hydrodynamic Testing

A computer-aided method of defining and machining 2-metre ship hull forms for hydrodynamic testing is described. The hull shape is faired from the original table of off-sets using a minimum number of smooth three-dimensional parametric skeletal-lines along the length of the boat. A fine set of smoothly blending station-lines is therby formed. The hull shape is preformed in two halves through a lamination process and machined on a three-axis numerically controlled machining (CNC) centre. A carbide-tipped, end-milling cutter is directed along the closely spaced station-lines to rapidly form an accurate hull shape requiring a minimum of hand work. The fairing and machining programs, called G-surf, run on a personal computer and are used to transmit the data and control the CNC machine in real time. The resulting hull shape is symmetrical and far more accurate than manually lofted and preshaped models.

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