Accession Number : AD0410837

Title :   THE EFFECT OF SURGE, ADDED MASS, AND UNSTEADY LIFT ON THE MOTION OF A HYDROFOIL BOAT IN A SEAWAY,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE

Personal Author(s) : Leopold,Reuven

Report Date : JAN 1963

Pagination or Media Count : 90

Abstract : Due to the large amount of computations involved in solving the equations of motion of a hydrofoil craft in a seaway, various simplified methods have been used in the past. Most of the methods fol lowing aircraft motions analyses were neglecting surge and added mass. It is shown that surge has a large effect on the heave and pitch motions while added mass and unsteady lift do not have significant effect. Furthermore, a boat with fully submerged foils can, in fact, be controlled through regular and irregular waves in both ahead and following seas. A computer program enabling very rapid evaluation of the motions through various seaconditions was prepared for IBM 7090 computer and the results were displayed on the television scope attached to the computer. Repro ductions of the results are presented. (Author)

Descriptors :   (*HYDROFOIL CRAFT, HYDRODYNAMICS), (*HYDRODYNAMICS, LIFT), SEA WATER, WATER WAVES, SEA BREEZE, VELOCITY, BESSEL FUNCTIONS, TAYLOR'S, NUMERICAL ANALYSIS, COMPUTERS, OSCILLO, PROGRAMMING (COMPUTERS), MOTION, HYDRO, FOILS(MATERIALS), ACCELERATION, DRAG, OSCILLATION, ANGLE OF ATTACK.

Distribution Statement : APPROVED FOR PUBLIC RELEASE