Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Experimental and Numerical Investigation of the Hydrodynamic Effect during the Ice Floe-structureInteraction
Guiyong Zhang1, 2*, Yu Zhao1, Biye Yang1, Zhe Sun1
1 State Key Laboratory of Structural Analysis for Industrial Equipment, School of Naval Architecture, Dalian University of Technology, Dalian,China
2 Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai, Chinaal., 2017). Because the hydrodynamic effects have a significant influenceon the interaction between structures and ice floes (Gagnon, 2004), theunquantified hydrodynamic interaction may be the reason for the
obvious reduction of the load. Sayeed et al. (2017) pointed out that thehydrodynamic interaction had a significant influence on the impact
velocity and eccentric impact of ice floes. Among them, the impact
velocity is an important factor for the impact load estimation (Duthinh,1989; Isaacson and Della Stritto, 1986), but at present, the understandingof ice floes’ velocity attenuation when approaching structures is still very
limited. Many studies simplified the hydrodynamic effects without
considering the influence of hydrodynamic pressure effects and damping(Gao et al., 2014).

ABSTRACTThe interaction between ice floes and marine structures is an important
issue for the safety of polar ships. However, the understanding ofhydrodynamic interaction between ice floes and structures during thecollision is not comprehensive, which usually leads to the wrong
estimation of impact velocity and impact load. In this paper, thehydrodynamic interaction between ice floe and fixed cylinder is studied
experimentally and numerically. In the experiment, the ice floe is driven
by uniform flow, and Qualisys optical 3D motion capture camera,
acceleration sensor, and impact force sensor are used to record andanalyze the data of the collision process. On this basis, the CFD-FEM
method is used to study the numerical results. The results show that thenumerical results calculated by CFD-FEM are in good agreement withthe experimental results. Under the hydrodynamic interaction, thevelocity of ice floe decreases significantly when it approaches thecylinder.

The potential flow model is used by some scholars to study relatedproblems. Tsarau et al. (2014) conducted an experiment of cylindricalstructures passing through a fixed ice mass at various velocities andseparation distances. The viscous effects were considered the possible
reasons for inconsistent results under the condition of small separation
distance. Kazi et al. (1998) used the potential flow model to simulate thehydrodynamic interaction between a fixed cylinder and free floating
cylinders and compared it with the experimental results. It wasconsidered that the potential flow model could predict the velocity of thefloating body well, but overestimated the force acting on the fixedcylinder. Ignoring the viscosity effects might be one of the key factors tocause the difference. Therefore, it is significant to use the viscous flow
model for solving such problems.

KEY WORDS: ice floe, hydrodynamic interaction; collision;
experimental study; CFD-FEM method; floe velocity.

INTRODUCTION
The Arctic is rich in natural resources with 13% unexplored oil reserves,
30% undeveloped natural gas reserves, and 9% coal resources (Bird etal., 2008). With the increase of global temperature, the area of sea ice in
the Arctic is decreasing at a rate of 13.1% every 10 years (Perovich et al.,2020), which provides convenient conditions for the exploitation of
Arctic resources. At the same time, it also promotes the development of
the Northern Sea Route and the North-West passage, which can reduce
the shipping time and cost between the Pacific Ocean and the AtlanticOcean. Sea ice floes are an important factor for the navigation andoperation of marine structures in polar regions. Marine structures haveto face the ice floes with large energy generated by flow and waves. Once
ice floes impact structures, it will bring great risks to the safety andoperation of marine structures. Therefore, it is one of the focuses to study
the interaction between ice floes and marine structures in related fields.

In this paper, the experiment and CFD-FEM coupled model have been
conducted to study the hydrodynamic interaction between ice floe andfixed cylinder. The purpose is to build an effective coupling model ofstructure-ice-water interaction based on CFD and FEM, and make apreliminary study on velocity attenuation in hydrodynamic interaction.
The experiment measures ice floe’s velocity, acceleration, and impact
force during the collision. The numerical simulation is in good
agreement with the experimental results, showing the experimentalprocess completely. Based on the experimental results, the velocity
attenuation before the impact is mainly discussed and analyzed.

Experimental results showed that the actual impact load between ice
floes and structures is always lower than the estimated values (Sayeed et1325