# ANALYSIS OF A LAMINATED COMPOSITE WIND TURBINE BLADE CHARACTERISTICS THROUGH MATHEMATICAL APPROACH

• CHOI, YOUNG-DO (DEPARTMENT OF MECHANICAL ENGINEERING, MOKPO NATIONAL UNIVERSITY) ;
• GO, JAEGWI (DEPARTMENT OF MATHEMATICS, CHANGWON NATIONAL UNIVERSITY) ;
• KIM, SEOKCHAN (DEPARTMENT OF MATHEMATICS, CHANGWON NATIONAL UNIVERSITY)
• Accepted : 2019.12.05
• Published : 2019.12.25

#### Abstract

A 1kW-class horizontal axis wind turbine (HAWT) rotor blade is taken into account to investigate elastic characteristics in 2-D. The elastic blade field is composed of symmetric cross-ply laminated composite material. Blade element momentum theory is applied to obtain the boundary conditions pressuring the blade, and the plane stress elasticity problem is formulated in terms of two displacement parameters with mixed boundary conditions. For the elastic characteristics a fair of differential equations are derived based on the elastic theory. The domain is divided by triangular and rectangular elements due to the complexity of the blade configuration, and a finite element method is developed for the governing equations to search approximate solutions. The results describe that the elastic behavior is deeply influenced by the layered angle of the middle laminate and the stability of the blade can be improved by controlling the layered angle of laminates, which can be evaluated by the mathematical approach.

#### Acknowledgement

Supported by : National Research Foundation of Korea (NRF)

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