Session: 07-04-01 Ships and Structures in Ice

Submission Number: 179643

A Parametric Study on Ship-Ice Interaction With Fully Eulerian Phase-Field Framework 

As the Arctic Ocean is becoming increasingly navigable owing to the shrinking ice cover, the region has garnered strategic interests for shipping activities. While polar sea routes can connect continents via a fraction of the distance of traditional shipping routes, the Arctic region is perilous for safe and efficient shipping. The development of robust ice-going ships and effective powering margins is [r1] an emerging application of multiphase fluid-structure interaction. Ship-ice interactions involve complex and coupled nonlinear dynamics that are challenging to predict and sufficiently analyze via experimental methods. Although crucial for hull and operation design optimization, parametric investigations across a realistic range are particularly challenging. High-fidelity numerical models for the dynamics arising in ship-ice interactions on a free surface are therefore imperative in the advancement of safe and efficient Arctic shipping.

Ship-ice interaction is a complex system wherein floating structures and multibody collisions are coupled. Conventional numerical methods to model ship-ice interaction find their limitations in coupling fluids and solids conservatively, particularly for hydrodynamically mediated multibody collisions. CFD-DEM is typically employed to simulate ship interaction with a field of floating ice floes. However, the feedback from structures on the fluid is conventionally neglected and modeling ice properties require empirical tuning. While LS-DYNA allows modeling structural collision coupled with hydrodynamics based on continuum mechanics, there are limitations in energy conservation in modeling the fluid-structure interaction (FSI). A multiphase fully Eulerian framework is therefore well-suited to model ship-ice interaction that is strongly coupled to the free-surface flow. A novel multiphase fully Eulerian framework employing a phase field formulation to describe interfaces has been developed [1]. The continua of all fluid and solid phases are modeled on a spatially fixed mesh, thereby naturally enabling large structural motion, deformation and collision without mesh distortion. Its comprehensive force analysis framework enables systematic parametric investigations relevant to Arctic shipping.

In this paper, we investigate the effects of key parameters on submerged collision dynamics and ship-ice interaction with free-surface effects. The parameters investigated represent a broad range of ice interaction scenarios that an ice-going vessel must be designed to withstand. A submerged steel ball impacting an ice block underwater is examined to represent thrusters or bulbous bow colliding with ice. Since sea ice shear modulus varies with temperature and salinity, we explore a range of ice shear modulus to represent seasonal variation in first-year ice or multiyear ice that polar vessels can encounter. Extending the setup to a realistic ship-ice interaction case, we present how geometric properties of ice floes affect the load on a container ship as it traverses a floating ice floe field. Broken ice field can feature ice floes of diverse sizes, leading to variation in impulse and hydrodynamic shielding. Understanding the sensitivity of ice load on ships to ice properties is essential in designing robust polar class vessels. Furthermore, examining the effect of impact speed on ice loading can inform safe powering margins for polar ships to navigate a given ice field.

 

References

[1] Mao, Xiaoyu, Rath, Biswajeet and Jaiman, Rajeev. “A 3D phase-field based Eulerian variational framework for multiphase fluid–structure interaction with contact dynamics.” Computer Methods in Applied Mechanics and Engineering Vol. 429 (2024)

Presenting Author: Sabiha Bhuiyan The University of British Columbia

Presenting Author Biography: Sabiha is a graduate student at The University of British Columbia under mechanical engineering specializing in CFD and FSI simulations with application to ship-ice interaction.

Authors:

Sabiha Bhuiyan The University of British Columbia
Biswajeet Rath The University of British Columbia
Xiaoyu Mao The University of British Columbia
Rajeev Jaiman The University of British Columbia