Accession Number : AD0650513

Title :   SERIES INVESTIGATION OF SLAMMING PRESSURES,

Corporate Author : DAVID TAYLOR MODEL BASIN WASHINGTON D C

Personal Author(s) : Bledsoe,Margaret D.

Report Date : DEC 1956

Pagination or Media Count : 86

Abstract : The report presents the results of a theoretical investigation to determine the pressure distribution over the bottom of a slamming ship at zero forward speed when the impact with the still water surface results from a simple rotation in the plane of symmetry. A systematic series was used in order that some information concerning pressure dependence on hull shape might be obtained. The pressures were derived on the assumption that the vessels were all subject to the same rigid body velocities and accelerations. These pressures are presented in the form of plots showing the pressure distribution at various times after impact over the transverse sections of the forward 25 percent of the ships' lengths. The analysis indicates that the magnitude of the maximum pressures decreases and the region experiencing the highest pressures shifts aft with decreasing block coefficient (or increasing fineness). In particular, for a block coefficient of 0.80, the highest pressures were found to occur at approximately 10 percent of the ship's length aft of the forward perpendicular; for a block coefficient of 0.70, the region of highest pressures occurred at 22.5 percent of the ship's length. The magnitude of the maximum pressures experienced a 10-percent decrease for this change in block coefficient. (Author)

Descriptors :   (*SHIP HULLS, *IMPACT SHOCK), FLUID DYNAMICS, PRESSURE, SHIPS, DISTRIBUTION

Subject Categories : Marine Engineering
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE