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Nondestructive Evaluation of the Turbine Blade of Wind Energy By Using T-Ray

T-ray를 이용한 풍력터빈 브레이드 비파괴결함평가

  • Received : 2011.10.26
  • Accepted : 2012.02.01
  • Published : 2012.02.15

Abstract

A study of terahertz waves (T-ray) was made for the nondestructive evaluation of FRP (Fiber reinforced plastics) composite materials. The to-be-used systems were time domain spectroscopy (TDS) and continuous wave (CW). The composite materials investigated include both turbine blades of wind energy (non-conducting polymeric composites) and conducting carbon fiber composites. Terahertz signals in the TDS mode resembles that of ultrasound; however, unlike ultrasound, a terahertz pulse was not able to detect a material with conductivity. This was demonstrated in CFRP (Carbon fiber reinforced plastics) laminates. Refractive index (n) was defined as one of mechanical properties; so a method was solved in order solve the "n" in the material with the cut parts of the turbine blades of wind energy. The defects and anomalies investigated by terahertz radiation were foreign material inclusions and simulated disband. Especially, it is found that the T-ray went through the turbine blade with greater thickness (about 90mm).

Keywords

References

  1. Chiou, C. P., Blackshire, J. L., Thompson, R. B., and Hu B. B., 2009, "Terahertz Ray System Calibration and Material Characterzations," Review of QNDE, Vol. 28, pp. 410-417.
  2. Huber, R., Brodschelm, A., Tauser, A., and Leitenstorfer, A., 2000, "Generation and Field-Resolved Detection of Femtosecond Electromagnetic Pulses Tunable up to 41 THz," Appl. Phys. Lett., Vol. 76, pp. 3191-3199. https://doi.org/10.1063/1.126625
  3. Rudd, J. V., and Mittleman, D. M., 2000, "Influence of Substrate-lens Design in Terahertz Time-Domain Spectroscopy," J. Opt. Soc. Amer. B, Vol. 19, No. 2, pp. 319-329.
  4. Hsu, D. K., 1985, "Characterization of a Graphite/Epoxy Laminate by Electrical Resistivity Measurements," Rev. Prog. in Quantitative NDE, Vol. 4, Plenum Press, pp. 1219-1228.
  5. Habalia S. M., and Salehb L. A., 2000, "Local Design, Testing and Manufacturing of Small Mixed Airfoil Wind Turbine Blades of Glass Fiber Reinforced Plastics Part I: Design of the Blade and Root," Energy Conversion & Management, Vol. 41, pp. 249-280. https://doi.org/10.1016/S0196-8904(99)00103-X
  6. Chakrapani, S. K., Dayal, V., Hsu, D. K., Barnard, D. J., and Gross, A., 2011, "Characterization of Waviness in Wind Turbine Blades Using Air Coupled Ultrasonics," Review of Progress in QNDE, Vol. 30, pp. 956-962.
  7. Schueler, R., Joshi, S. P., and Schulte, K., 2001, "Damage Detection in CFRP by Electrical Conductivity Mapping," Composite Science and Technology, Vol. 61, No. 6, pp. 921-930. https://doi.org/10.1016/S0266-3538(00)00178-0
  8. Tse, K. W., Moyer, C. A., and Arajs, S., 1981,"Electrical Conductivity of Graphite Fiber epoxy Resin Composites," Materials Science and Engineering, Vol. 49, pp. 41-46. https://doi.org/10.1016/0025-5416(81)90131-2
  9. Im, K. H., Zhang, G. L., Choi, S. R., Ye, C. H., Ryu, J. S., Lim, S. H., Han, M. G., and Hsu, D. K., 2011, "One-Sided Nondestructive Evaluation of CFRP Composites By Using Ultrasonic Sound," Journal of the Korean Society of Machine Tool Engineers, Vol. 20, No. 1, pp. 47-52.