A Methodology for Measuring Blade Clearance on an Operating Utility-Scale Wind Turbine

Roadman, Jason [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000322805996); Bortolotti, Pietro [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000285159488); Fingersh, Lee Jay [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000348168331); Ivanov, Chris [National Laboratory of the Rockies (NLR), Golden, CO (United States)]; Iverson, Mark [National Laboratory of the Rockies (NLR), Golden, CO (United States)]; Jager, David [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000237980087); Slaughter, Derek [National Laboratory of the Rockies (NLR), Golden, CO (United States)]; Thao, Simon [National Laboratory of the Rockies (NLR), Golden, CO (United States)]; van Dam, Jeroen [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000337488284)

doi:10.2172/3023056

DOE OSTI · 3023056

A Methodology for Measuring Blade Clearance on an Operating Utility-Scale Wind Turbine

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Abstract

This report describes the deployment of eleven laser sensors to measure the clearance between blades and tower in a 1.5-MW wind turbine whose rotor was mounted first in upwind and then in downwind configurations. The experimental recordings are compared to the numerical predictions generated by an aeroservoelastic model of the turbine. Good agreement is found between the two datasets, although discrepancies up to 30~cm are observed. The sources of this error are discussed. This methodology is found to be a valuable resource for the validation of the numerical predictions of the flapwise deflections of wind turbine blades. The accurate prediction of these deflections is increasingly important as wind turbines grow in size and become increasingly flexible.

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Roadman, Jason [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000322805996), Bortolotti, Pietro [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000285159488), Fingersh, Lee Jay [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000348168331), Ivanov, Chris [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Iverson, Mark [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Jager, David [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000237980087), Slaughter, Derek [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Thao, Simon [National Laboratory of the Rockies (NLR), Golden, CO (United States)], van Dam, Jeroen [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000337488284). 2026-03-09. A Methodology for Measuring Blade Clearance on an Operating Utility-Scale Wind Turbine. https://doi.org/10.2172/3023056

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