Study on Method of Vibration Analysis for Ship Design : 4th Report

Abstract

Database method proposed by authors in the previous paper were applied for vibration response problems of a fore-and-aft vibration of superstructure. As an object of investigation, Accelerance (Acceleration per unit exciting force at peak frequency) at Navigation bridge deck was selected to remove difficulty and uncertainty of estimation for an exciting forces. General method to construct Database from vibration test results of existing ships was described. Various variables concerning to vibration characteristics of superstructure and ship hull were examined as an expression of empirical formula by regression analysis. It was found that √^3<l_m/H> and l_m/H^2 (l_m=mean side wall length, H=height excepting poop deck) indicate comparably better factor to regression line of Accelerance of superstructure.