Design and analysis of vertical axis thermoplastic composite wind turbine blade

Abstract

There is growing interest in the use of thermoplastic composites for wind turbine blades. This paper presents preliminary work on the design, analysis and manufacture of a thermoplastic composite blade for a vertical axis wind turbine. The blade design featured a sandwich construction with commingled woven E-glass fibre/polypropylene thermoplastic composite skins and a polyethylene terephthalate (PET) foam core. A finite element modelling methodology has been developed for predicting the natural frequency and structural performance of the blade. For structural analysis, the skin was modelled with a composite damage model for which an inverse calibration procedure was developed. Vibration and static bending tests were conducted on a subscale prototype blade to validate the finite element models. A one-step vacuum moulding process was adopted to manufacture the prototype blade. The validated finite element models were then used to determine the natural frequency of the full sized blade and predict its performance under in-service aerodynamic loads. The results show that the thermoplastic composite blade design meets the desired structural requirements.