Study on Air Bubble Defect Evolution in Wind Turbine Blade by Infrared Imaging with Rheological Theory

Applied Sciences

He Li¹  Bo Zhou²  Xueyan Zhang³ 

[1] Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education, Northeastern University, Shenyang 110819, China;School of Architecture and Civil Engineering, Shenyang University of Technology, Shenyang 110870, China;School of Mechanical Engineering, Shenyang University of Technology, Shenyang 110870, China;

关键词: glass fiber reinforced plastic;    air bubble defects;    infrared thermal imager;    temperature jump;    critical time;    macroscopic crack;   

DOI  :  10.3390/app9224742

来源: DOAJ

【 摘 要 】

Air bubble is a manufacturing defect that is common to composite wind turbine blades, which might evolve into cracks, leading to failure under load. The evolution and critical state of air bubble are studied to establish a condition assessment method for blade quality control. A method that is based on rheological theory is proposed to recognize the critical state by temperature jump. The air bubble is regarded as a null set and the temperature distribution of bubble defect is affected by the volumetric strain energy under tensile load. An infrared camera can detect a temperature jump when mechanical characteristics drastically change due to crack formation. A tensile fatigue test was carried out to verify the accuracy of this method. The relative error between the measured and calculated temperature rise at the critical moment was less than 7%. Additionally, the specimen with [0/90]_s ply angles is more favorable to maintain the structural stability than the others. The method in this paper establishes a quantitative relationship between the meso-defect and macro mechanical properties. The defect severity of wind turbine blade can be defined by infrared imaging technology.

【 授权许可】

Unknown