Numerical Analysis of Hydrodynamic Loads on Passing and Moored Ships in Shallow Water

Ji-Yong Park,Bo Woo Nam,Yonghwan Kim

doi:10.3390/pr9030558

Abstract

In this study, hydrodynamic interactions between passing and moored ships were studied by applying a time-domain numerical simulation method. The boundary value problem for a fluid domain was formulated based on a potential flow theory. A numerical method was developed based on a finite element method with an efficient re-mesh algorithm. Regarding the free-surface boundary conditions, both double-body and free-surface models were considered for examining the free-surface effect on the hydrodynamic forces due to the passing ship. First, numerical results were validated by comparison with the model test results of Kriebel et al. (2005), where generic Series 60 hulls were considered as the target model for the passing and moored ships. In addition, hydrodynamic pressure fields and force time-series were investigated to understand the passing ship problem. Second, a series of numerical simulations were performed to study the effects of the passing ship speed, separation distance, water depth, and relative vessel size, which were used to compare the peak values of hydrodynamic forces. The applicability and limitations of the double-body and free-surface models are discussed for predicting passing ship loads.

Highlights

IntroductionIn ports or coastal areas, an advancing ship is often observed to pass near moored or anchored ships
We investigated the passing ship problem in order to predict the hydrodynamic forces acting on a moored ship resulting from a passing ship
The hydrodynamic forces acting on a moored ship were calculated when a passing ship travels far from the moored ship and moves parallel to it

Summary

Introduction

In ports or coastal areas, an advancing ship is often observed to pass near moored or anchored ships. As the speed and size of ships have increased recently, the effect of large and high-speed passing ships has become an important consideration for the safety of moored ships. It is known that significant changes in the hydrodynamic pressure field around a passing ship can cause an excessive horizontal motion in moored ships, which, in turn, may result in collisions with other ships or the quay wall. In the worst-case scenario, damage to a berthing or offloading ship’s mooring and mechanical equipment could result in a massive explosion and injuries [1]. For the safe design of the mooring system of anchored vessels or the establishment of reasonable operating regulations—such as the passing ship speed and separation distance—

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Results

Conclusion