Application of Higher-Order Spectral Analysis Method to the Estimation of Added Resistance in Waves

Abstract

Cross-bi-spectral analysis method, the second order spectral analysis method, is applied to the analysis of response characteristics of added resistance in waves. The method was firstly developed by Dalzell under an assumption that resistance of ships in waves can be represented by a functional polynominal truncated upto second order terms with respect to incident wave height. By making use of results of resistance tests in irregular head waves, cross-bi-spectra and response characteristics are analyzed for two ship models. An analytical method is developed after Dalzell and Kim in order to analyze the response characteristics of added resistance in bi-frequency domain. Experimental and numerical results are compared with each other, and as the results of the study, it can be said that the cross-bi-spectral analysis method. is applicable to the analysis of added resistance of ships in waves.