Journal of Advanced Engineering and Technology (공학기술논문지)

Engineering Technology Institute of Chosun University (조선대학교 공학기술연구원)
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NDE Inspecting Techniques for Wind Turbine Blades Using Terahertz Waves

테라헤르츠파를 이용한 풍력터빈 블레이드 NDE 탐상 평가기법

  • Im, Kwang-Hee (Department of Automotive Eng., Woosuk University) ;
  • Kim, Sun-Kyu (Division of Mech. System Eng., Chonbuk Natl. University) ;
  • Jung, Jong-An (Dept. of Mechanical and Automotive Engineering, Songwon University) ;
  • Cho, Young-Tae (Dept. of Basic Science, Jeonju University) ;
  • Woo, Yong-Deuck (Department of Automotive Eng., Woosuk University)
  • 임광희 (우석대학교, 기계자동차공학과) ;
  • 김선규 (전북대학교 기계시스템공학과) ;
  • 정종안 (송원대학교 기계자동차공학과) ;
  • 조영태 (전주대학교 기초과학과) ;
  • 우용득 (우석대학교, 기계자동차공학과)
  • Received : 2018.10.01
  • Accepted : 2018.12.20
  • Published : 2018.12.31

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Abstract

Terahertz waves (T-ray) was extensively studied for the NDE (nondestructive evaluation) of characterization of trailing edges for a use of turbines composed with composite materials. The used NDE system were consisted of both CW(Continuous wave) and TDS (Time domain spectroscopy). The FRP composites were utilized for two kinds of both trailing edges of wind energy (non-conducting polymeric composites) and carbon fiber composites with conducting properties. The signals of T-ray in the TDS (Time domain spectroscopy) mode resembles almost that of ultrasound waves; however, a terahertz pulse could not penetrate a material with conductivity unlike ultrasound. Also, a method was suggested to obtain the "n" in the materials, which is called the refractive index (n). The data of refractive index (n) could be solved for the trailing edges. The trailing edges were scanned for characterization and inspection. C-scan and B-scan images were obtained and best optimal NDE techniques were suggested for complicated geometry samples by terahertz radiation. Especially, it is found that the defect image of T-ray corresponded with defect locations for the trailing edges of wind mill.

Keywords

Acknowledgement

Supported by : National Research Foundation of Korea (NRF)

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