A note on ratio-of-polynomials curve-fitting of seawave spectra

Abstract

Seawave spectra are described in mathematical form normally by Pierson-Moskowitz-type distributions.

Unfortunately the equations arising from such descriptions are difficult to manipulate in analytical investigations. In other branches of engineering analysis it is common to take a ratio-of-polynomials form as mathematical representations of spectral distributions. Such forms have been studied in much detail and are well documented in the literature. In this note we show how seawave-type spectra may be fitted by the ratio-of-polynomials form in a simple way by an adaptation of a method due to Sanathanan and Koerner [5].