Validation of Container Ship Squat Modeling Using Full-Scale Trials at the Port of Fremantle

Abstract

In this paper, selected results are presented from a set of recent full-scale trials measuring the dynamic sinkage, trim, and heel of 16 container ship transits entering and leaving the Port of Fremantle, Western Australia. Measurements were made using high-accuracy Global Navigation Satellite System (GNSS) receivers and a fixed reference station. The measured dynamic sinkage, trim, and heel of three example container ship transits are discussed in detail. Maximum dynamic sinkage and dynamic draught, as well as elevations of the ship’s keel relative to chart datum, are calculated. A theoretical method using slender-body shallow-water theory is applied to calculate sinkage and trim for the transits. It is shown that the theory is able to predict ship squat (steady sinkage and trim) with reasonable accuracy for container ships at full scale in open dredged channels. In future work, the measured ship motions, along with full measured wave time series data, will be used for validating wave-induced motion software.