Geometrical variation and distortion of ship hull forms

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.