Available at: http://digitalcommons.calpoly.edu/theses/154
Date of Award
MS in Mechanical Engineering
A detailed study of the fatigue life of wooden wind turbine blades for a new 10 kilowatt system was undertaken. A numerical model of the blades was created using the technical software package MATLAB in order to estimate the maximum stress occurring within the blade in response to changes in wind velocities based on a wind profile approximating the location where these turbines are expected to operate. The material properties of the wooden laminate were measured using an Instron tensile test machine and were found to be in line with published values. In parallel with this effort, a three dimensional part scanner was utilized to compare the as-built blade to the theoretical profile and large differences between these two profiles were observed. These studies were then used to guide the creation of a full scale fatigue test which subjected two blades to accelerated fatigue loads in order to monitor the damage accumulation within each blade. It was ultimately determined that this new blade design has a fatigue life greater than 20 years.