Abstract

Hydrofoils are wing-shaped submerged structures designed to lift a vessel's hull above the water's free surface during motion, thereby reducing hydrodynamic drag. This advanced technology is widely employed in marine engineering to improve speed and reduce fuel consumption. Analysing hydrofoil dynamics requires considering the interaction with both water and air. While air resistance is often neglected in practical applications due to its minimal contribution to overall drag in stable operating conditions, it can significantly influence the system in transient scenarios such as abrupt changes of angle of attack or gusty wind conditions.

The present investigation focuses on a 3D numerical comparative analysis of two approaches to fluid-structure interaction: a two-fluid model incorporating both air and water and a simplified one-fluid model considering water alone. Within this framework, a partitioned approach is employed to address the fluid-structure interaction problem, where the solid subproblem is investigated using the out-of-the-shelf solver Abaqus/Standard. The coupling at the interface between the fluid and the structure is managed using quasi-Newton schemes, which are specifically designed to enhance computational efficiency by reducing the number of iterations required to achieve convergence. Additionally, hydrofoils are modelled using advanced composite materials to improve their strength and enhance their lightweight properties.

By evaluating the performance and accuracy of the two-fluid and one-fluid models, this work aims to provide insights into the conditions under which air-fluid interactions significantly impact structural behavior and determine conditions under which the one-fluid approximation provides reliable results while optimizing computational resources. 
 

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Speaker

Daniele Di Cristofaro is a PhD Student in Structural Seismic and Geotechnical Engineering at Politecnico di Milano, within the structure section. In 2022, he obtained a master’s degree in mathematical engineering at Politecnico di Milano. 
Currently, he is working on in-depth research specifically geared towards Fluid-Structure-Interaction numerical schemes involving thin and lightweight structures, which can be effectively treated using shell solid mechanics theory.
Daniele likes to spend his free time swimming, reading and travelling.

Daniele Di Cristofaro
PhD Student
Politecnico di Milano