Aeroelastic Analysis of the LMH64-5 Blade Concept

摘要

Within the DOWEC project, investigations were performed into the development of large size wind turbines for offshore applications. Many of the studies in this project were performed for a 6MW concept of which the turbine was designed by NEG-Micon Holland and the LMH64-5 blade by LM Glasfiber Holland. One of the tasks within this project was to investigate the aeroelastic stability problems for large size wind turbines which was performed for this 6MW concept. These analyses were done with the program BLADMODE. This document starts with a description of the modelling of the blade in basis of a set of 51 files with the cross sectional layout. For the first bending modes the direction of blade motion 'theta' was calculated for the rotating and non-rotating state, which can be used as input for hingespring- damper analysis tools. The operational conditions as function of wind speed for which the aeroelastic stability was investigated, were calculated with the program PHATAS. The aerodynamic damping was calculated for the original LMH64-5 blade concept, and also for some parameter variations on structural and aerodynamic modelling aspects and on the so-called 'Structural Pitch'. Finally a comparison was made of the aeroelastic damping calculated with the original LMH64-5 geometry and a tapered variant.