Self-heating forecasting for thick laminate specimens in fatigue

The Science of Making Torque from Wind 2012

Lahuerta, F.^1 ; Westphal, T.^1 ; Nijssen, R.P.L.^1

Knowledge Centre WMC, Wieringerwerf

1770 AA, Netherlands^1

关键词: Conductivity properties;    Energy loss ratio;    High temperature gradient;    Laminate thickness;    Mechanical loading;    Premature failures;    Surface temperature measurement;    Wind turbine blades;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/555/1/012062/pdf
DOI  :  10.1088/1742-6596/555/1/012062

来源: IOP

【 摘 要 】

Thick laminate sections can be found from the tip to the root in most common wind turbine blade designs. Obtaining accurate and reliable design data for thick laminates is subject of investigations, which include experiments on thick laminate coupons. Due to the poor thermal conductivity properties of composites and the material self-heating that occurs during the fatigue loading, high temperature gradients may appear through the laminate thickness. In the case of thick laminates in high load regimes, the core temperature might influence the mechanical properties, leading to premature failures. In the present work a method to forecast the self-heating of thick laminates in fatigue loading is presented. The mechanical loading is related with the laminate self-heating, via the cyclic strain energy and the energy loss ratio. Based on this internal volumetric heat load a thermal model is built and solved to obtain the temperature distribution in the transient state. Based on experimental measurements of the energy loss factor for 10mm thick coupons, the method is described and the resulting predictions are compared with experimental surface temperature measurements on 10 and 30mm UD thick laminate specimens.