Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Effect of Insulation Coating on Start Time of Linear Region for Transient Hot-wire Method

비정상열선법에서 열선의 절연코팅이 선형구간의 초기시점에 미치는 영향

  • Lee, Seung-Hyun (School of Mechanical and Aerospace Engineering, Korea Aerospace Univ.) ;
  • Kim, Hyun Jin (School of Mechanical and Aerospace Engineering, Korea Aerospace Univ.) ;
  • Kim, Kyu Han (School of Mechanical and Aerospace Engineering, Korea Aerospace Univ.) ;
  • Park, Yong-Jun (School of Mechanical and Aerospace Engineering, Korea Aerospace Univ.) ;
  • Jang, Seok Pil (School of Mechanical and Aerospace Engineering, Korea Aerospace Univ.)
  • 이승현 (한국항공대학교 항공우주 및 기계공학부) ;
  • 김현진 (한국항공대학교 항공우주 및 기계공학부) ;
  • 김규한 (한국항공대학교 항공우주 및 기계공학부) ;
  • 박용준 (한국항공대학교 항공우주 및 기계공학부) ;
  • 장석필 (한국항공대학교 항공우주 및 기계공학부)
  • Received : 2013.09.17
  • Accepted : 2013.10.02
  • Published : 2013.12.01
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Abstract

In this study, the effect of an insulation coating on the start time of a linear region is theoretically investigated when an insulation-coated hot-wire is used for the transient hot-wire method (THWM). For this purpose, important parameters affecting the start time of the linear region are presented from an analytical solution of temperature-rise for an insulation-coated hot-wire. Furthermore, a critical time to ignore the influence of important parameters is studied. The theoretical results indicate that the effect of the insulation coating rapidly disappears with a decrease in the wire radius, coating thickness, thermal diffusivity of insulation material or an increase in the thermal conductivity of the insulation material. The results of this study will be helpful for selecting a proper start time of the linear region for the THWM using insulation-coated hot-wires.

본 논문에서는 절연된 열선을 이용한 비정상열선법에서 열선의 절연코팅이 선형구간의 초기시점에 미치는 영향을 살펴보기 위하여 이론적인 연구를 수행해 보았다. 이를 위해, 절연된 열선의 온도상승에 관한 해석적 해에서 선형구간의 초기시점에 영향을 미치는 중요한 인자들을 파악해 보았으며, 이러한 인자들의 영향이 무시할 만큼 작아지는 임계시간(critical time)에 대한 연구를 수행해 보았다. 이론적인 연구 결과, 열선의 반경 및 코팅의 두께가 작을수록 절연코팅의 영향이 빠르게 감소하였고, 또한 절연물질의 열전도도가 크고 열확산계수가 작을수록 절연코팅의 영향이 빠르게 감소함을 알 수 있었다. 본 연구의 결과는 절연된 열선을 이용한 비정상열선법에서, 선형구간의 초기시점을 결정하는데 도움이 될 것으로 사료된다.

Keywords

References

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