Early-Stage Investigation of Environmentally Friendly Sliding Bearings for Offshore Wind Turbine Main Shafts

• Autorzy: Wasilczuk Filip , Wasilczuk Michał , Flaszyński Paweł , Litwin Wojciech

Identyfikatory

DOI

10.2478/pomr-2025-0059

• Języki publikacji: EN

Abstrakty

EN

This work presents a preliminary assessment of the potential application of water-lubricated radial sliding bearings as main shaft bearings in large offshore wind turbines. The study is driven by the environmental concerns and the high cost and size associated with conventional rolling element bearings. Four bearing material candidates were examined: lignum vitae, a compliant elastic polymer, a three-layer PTFE-based composite, and a fibre-reinforced polymer. Pilot experiments were carried out on a custom-built test rig capable of accurately capturing friction torque under controlled radial loads, with freshwater serving as both lubricant and coolant. The procedure included a defined running-in phase and multiple repeated tests to ensure reproducibility. The sliding speed and load conditions were determined using a combination of multi-body dynamic simulations of the IEA 15 MW reference turbine and published load analyses, ensuring that the test conditions reflect realistic operating values. The results showed that the polymer and PTFE-based composite exhibited excellent tribological behaviour, maintaining very low friction coefficients during both steady and start-up operation. Although the wear behaviour was not quantified at this stage, the low friction coefficients indicate operation in a full hydrodynamic lubrication regime, which is expected to minimise wear. Overall, this preliminary investigation suggests that selected water-lubricated sliding bearings represent a promising, environmentally friendly alternative for offshore wind turbine main shafts, offering advantages in corrosion resistance, durability under dynamic loading, and potentially low wear.

Słowa kluczowe

EN

wind turbine bearing; low-speed sliding bearing; energy efficiency; journal bearings experimental tests

• Wydawca: Gdańsk University of Technology, Faculty of Ocean Engineering & Ship Technology
• Czasopismo: Polish Maritime Research
• Rocznik: 2025
• Tom: nr 4
• Strony: 157--167
• Opis fizyczny: Bibliogr. 42 poz., rys., tab.

Twórcy

autor

Wasilczuk Filip

• Institute of Fluid Flow Machinery, Polish Academy of Sciences, Fiszera 14 St., Gdańsk, Poland

• https://orcid.org/0000-0002-8658-5622

autor

Wasilczuk Michał

• Gdańsk University of Technology, Faculty of Mechanical Engineering and Ship Technology, 11/12 Narutowicza St., Gdańsk, Poland

• https://orcid.org/0000-0001-7683-9169

autor

Flaszyński Paweł

• Institute of Fluid Flow Machinery, Polish Academy of Sciences, Fiszera 14 St., Gdańsk, Poland

• https://orcid.org/0000-0002-4210-804X

autor

Litwin Wojciech

• Gdańsk University of Technology, Faculty of Mechanical Engineering and Ship Technology, 11/12 Narutowicza St., Gdańsk, Poland

• https://orcid.org/0000-0002-1787-229X

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