Experimental study into the effect of wind-ice misalignment on the development of ice-induced vibrations of offshore wind turbines

The effect of misalignment between wind- and ice loading direction on the development of ice-induced vibrations of offshore wind turbines has been investigated experimentally. In the experiments a hybrid test setup was used to study the structural response to combined loading from physical model ice and numerically applied wind. The...

Dynamic ice loads for offshore wind support structure design

For offshore wind farms which are planned in sub-arctic regions like the Baltic Sea and Bohai Bay, support structure design has to account for load effects from dynamic ice-structure interaction. There is relatively high uncertainty related to dynamic ice loads as little to no load- and response data of offshore wind turbines exposed to...

Dynamic Modelling of Ice Rubble and Extrusion Loads on Offshore Wind Turbines in Crushing Interaction

To accommodate the growing demand for renewable energy, installation of new offshore wind energy capacity is increasing in many countries. New projects will be proposed for waters in which floating (sea) ice is a common occurrence in winter. Currently, projects remain limited to regions with mild ice conditions, such as the Southern Baltic Sea,...

Ice-structure interaction in the Baltic Sea: defining a feasibility map for monopiles

The increasing popularity of offshore wind as a result of the demand for renewable energy, forces the industry to consider the development of wind farms in sub-arctic areas. One of these areas is the Baltic Sea, where the potential for wind energy is very large, but which is also prone to the occurrence of ice. For the design of offshore...

Experimental data from ice basin tests with vertically sided cylindrical structures

Basin tests were performed at the Aalto Ice Tank to gather data on ice-structure action and interaction from ice failing against a vertically sided cylindrical pile. The tests were performed with a real-time hybrid test setup, which combined physical and numerical components to simulate a range of test structures in real-time. The dataset...

Dynamic ice-structure interaction for jacket substructures

With a growing global demand of clean renewable energy, offshore wind activities will extend to more harsh environments, including sub-arctic areas like the Baltic Sea. Sea ice can occur here which needs to be taken into consideration in the design of substructures, i.e. jacket substructures, of offshore wind turbines. Several ice mitigating...

Two-dimensional ice-structure interaction for offshore wind turbines

With the Paris climate accords signed in 2016, most countries have committed themselves to ambitious climate targets during the next decades. One of these targets is a dramatic increase in the overall energy portfolio's market share of renewable energies. This increase in renewable market share will, for a large part, consist of newly built...

On pressure modes in ice-induced vibrations using multivariate analysis

Pressures at the ice-structure interface during model-scale ice-structure interaction are often measured with tactile sensors. Resulting datasets usually include large volume of data along with some measurement error and noise; therefore, it is inherently hard to extract the hidden fluctuating pressures in the system. Identifying the...

Stochastic subspace identification of modal parameters during ice–structure interaction

Identifying the modal parameters of structures located in ice-infested waters may be challenging due to the interaction between the ice and structure. In this study, both simulated data from a state-of-the-art ice–structure interaction model and measured data of ice–structure interaction were both used in conjunction with a covariance-driven...

The effect of hydrodynamics on the bending failure of level ice

In this paper, the bending failure of level ice caused by the interaction with a downward sloping structure is studied in 2D. The focus is on the effect of hydrodynamics on the interaction. This study is done by comparing the predictions of a model that includes both hydrostatics and hydrodynamics with one that only includes hydrostatics.<br/...

Operational modal analysis on a lighthouse structure subjected to ice actions

The sea ice interaction with a structure may cause system changes and affect the feasibility of common approaches to track modal parameters. In this paper, a covariance-driven stochastic subspace identification method is used to identify the natural frequencies from 190 time series of ice actions against a lighthouse structure. The results...

Ice-induced vibrations and ice buckling

Ice-induced vibrations can occur when flexible, vertically-sided offshore structures are subject to level ice such that the failure mode of ice is predominantly crushing. When the ice is relatively thin, or when the width of the structure is much larger than the ice thickness, the ice tends to buckle and subsequently fail as soon as the...

Model and parameter identification for nonlinear ice-structure interaction