IJSCT 163

Paper Title: Back Against the Wall

Authors

R J Dunworth, Department of Defence, Navy Engineering Division, Australia

Summary

An inclining experiment is the established method used to determine the vertical centre of gravity of a ship. At the same time, the other lightship properties can be found ¯ displacement and the longitudinal and transverse centres of gravity. Only in exceptional circumstances will the traditional method of calculating KG deliver a completely accurate value due to the dependence on wall-sided theory. Although the result may be acceptable for large vessels which tend to be wall sided (or nearly so) at the inclining waterplane, there can be significant error on small vessels which typically have more shape in that region. The problem is discussed and the magnitude of potential error is investigated. An alternative calculation method is proposed, with validity demonstrated by calculation and example. The method overcomes the drawbacks of the classic calculations and allows the evaluation of KG and TCG of any hull form, inclined to any angle of heel or trim. This paper expands on a previous paper, Up Against the Wall, by the author.

Reference

Transactions RINA, Vol 156, Part B2, International Journal of Small Craft Technology, Jul-Dec 2014 

DOI Number

DOI No: 10.3940/rina.ijsct.2014.b2.163

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