HYDRODYNAMIC THEORIES OF SHIP SLAMMING: REVIEW AND EXTENSION

A critical review and evaluation of existing hydrodynamic theories of body-water impact is presented. It is shown, partly by comparison with available experimental data, that current fitting methods are adequate only for bodies of reasonably large deadrise angle, particularly during the later stages of the impact process. An improved ellipse-fitting technique is presented that extends to a much broader class of body forms and derives more accurate formulations of the general problem. The refined technique avoids linearization of the free surface boundary condition and accounts for compressibility effects during the initial stage of impact. It is concluded that similar refined methods of predicting slamming pressures are necessary not only for critical ship design problems but also for the assessment of approximate theories used in studies of slamming characteristics of various ship forms.