Automated processing of free roll decay experimental data. (1st July 2015)

• Record Type: Journal Article
• Authors: Uzunoglu, E.; Guedes Soares, C.
• Is Part Of: Ocean engineering. Volume 102(2015)
• Page Start: 17
• Page End: 26
• Publication Date: 2015-07-01
• Subjects: Roll damping -- Free decay motion -- Experimental assessment -- Numerical methods; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2015.04.016
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: This work presents an efficient numerical and modular approach to assessing viscous roll damping coefficients from free decay tests. In order to reduce the time consumed during analysis, numerical pre-processing of the data without visual inspection is suggested. The method involves breaking down multiple decay motions recorded in a single time series, numerically determining the beginning and the end of valid decay motion, eliminating the outlying data from the experimental analysis and obtaining the linear and non-linear roll damping coefficients. None of the pre-processing steps depend on each other and they can be used separately in a modular structure. The process is exemplified using decay test samples of a fishing vessel. To use these analysis results in numerical simulations that extend beyond identical conditions with the experiments, a 3D surface approach is examined. The surface also reveals the effect of speed on the coefficients obtained from the sample set. Highlights: An automated approach to assessing viscous roll damping coefficients from free decay tests is described. The method involves breaking down multiple decay motions recorded in a single time series. It eliminates the outlying data from the experimental analysis. The process is exemplified using decay test samples of a fishing vessel.