PRELIMINARY EXPERIMENTAL INVESTIGATION OF SLAMMING,

Abstract

The results of experiments performed on a ship model to determine the impact forces on the bottom are analyzed and compared with previous theoretical investigations. It was found that by introducing the concept of equivalent deadrise angle and considering only the first few milliseconds of the impact (i.e., the period of the sudden deceleration), the theoretically predicted acceleration-time curve approximates the experimentally found curve sufficiently well for all practical purposes. On the basis of the few successfully performed experiments, the cautious statement can be made that the speed of advance does not seem to influence greatly either the maximum impact force or the time required to reach maximum deceleration. It is remarkable that the approximate formulae result in good agreement with the experiments performed. The experimental conditions were artificial since the impact was produced by dropping the model at very small (0.1 - 0.2 degree) trim angles. The results of these artificial experiments show very large impact forces. If the actual pitching motion of the ship is considered, the impact forces are much smaller. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1952
Accession Number
AD0649746

Entities

People

  • Samuel H. Brooks
  • Victor G. Szebehely

Tags

DTIC Thesaurus Topics

  • Agreements
  • Deceleration
  • Models
  • Motion
  • Physical Properties
  • Ship Models
  • Slamming
  • Trim Angle

Readers

  • Educational Psychology
  • Explosive Engineering.
  • Marine Hydrodynamics