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

The Korean Society of Mechanical Engineers (대한기계학회)
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Measurement of Critical Heat Flux Using the Transient Inverse Heat Conduction Method in Spray cooling

비정상 열전도 역산법에 의한 분무냉각 임계열유속(CHF)의 측정에 관한 연구

  • Kim, Yeung Chan (Dept. of Mechanical & Automotive Engineering, Andong Nat'l Univ.)
  • 김영찬 (안동대학교 기계자동차공학과)
  • Received : 2016.04.01
  • Accepted : 2016.07.10
  • Published : 2016.10.01
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Abstract

A study on the measurement of critical heat flux using the transient inverse heat conduction method in spray cooling was performed. The inverse heat conduction method estimates the surface heat flux or temperature using a measured interior temperature history. The effects of the measuring time interval and location of temperature measurement on the measurement of critical heat flux were primarily investigated. The following results were obtained. The estimated critical heat flux decreased as the time interval of temperature measurement increased. Meanwhile, the effect of measurement location on critical heat flux was not significant. It was also found, from the experimental results, that the critical superheat increased as the measurement location of thermocouple neared the heat transfer surface.

본 연구에서는 비정상 열전도 역산문제의 해석이 가능한 프로그램을 이용하여 온도측정의 시간간격, 측정위치가 분무냉각 열유속의 측정결과에 미치는 영향에 대한 연구를 수행하였다. 그 결과 다음과 같은 결론을 얻을 수 있었다. CHF 부근에서는 온도측정의 시간간격이 커질수록 비정상 열전도 역산법을 이용하여 계산한 열유속은 점차 감소하고 있음을 알 수 있었다. CHF 부근에서는 열유속이 매우 빠르게 변화하기 때문에 시간간격을 일정 값 이하로 작게 측정하여 열유속을 계산하는 것이 매우 중요할 것으로 판단된다. 온도측정위치는 비정상 열전도 역산법을 이용한 CHF 부근의 계산결과에 큰 영향을 미치지 않는 것으로 파악되었다. 실험결과로부터 CHF 과열도는 열전대의 측정위치가 전열면 표면에 가까울수록 약간 고온으로 이동하는 경향이 있음을 알 수 있었다.

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References

  1. Ohkubo, H. and Nishio, S., 1993, "Study on Mist Cooling for Heat Treatment of Metals," J. of Materials Processing & Manufacturing Science, Vol. 2, pp. 14-27.
  2. Yang, W. J. and Clark, D. W., 1975, "Spray Cooling of Air-cooled Compact Heat Exchangers," Int. J. of Heat & Mass Transfer, Vol. 18-2, pp. 311-317. https://doi.org/10.1016/0017-9310(75)90162-3
  3. Yamanouchi, A. 1968, "Effect of Core Spray Cooling in Transient State After of Coolant Accident," J. of Nuclear Science & Technology, Vol. 5-11 pp. 547-558. https://doi.org/10.1080/18811248.1968.9732513
  4. Sehmbey, Maninder S., Chow, Louis C., Hahn, Ottfried J. and Pais, Martin R., 1995, "Spray Cooling of Power Electronics at Cryogenic Temperature," J. of Thermo-physics & Heat Transfer, Vol. 9-1, pp. 123-128. https://doi.org/10.2514/3.637
  5. Aguilar, G., Majaron, B., Verkruysse, W., Zhou, Y., Nelson, J. S. and Lavernia, E. J., 2001, "Theoretical and Experimental Analysis of Droplet Diameter, Temperature, and Evaporation Rate Evolution in Cryogenic Sprays," Int. J. of Heat & Mass Transfer, Vol. 44, pp. 3201-3211. https://doi.org/10.1016/S0017-9310(00)00363-X
  6. Stolz, G., 1960, "Numerical Solutions to an Inverse Problem of Heat Conduction for Simple Shapes," J. of Heat Transfer, Vol. 82(C), pp. 20-26. https://doi.org/10.1115/1.3679871
  7. Beck, J. V., 1968, "Surface Heat Flux Determination Using an Integral Method, Nuclear Engineering Design," Vol. 1, pp. 170-178.
  8. Burggraf, O. R., 1964, "An Exact Solution of the inverse Problem in Heat Conduction Theroy and Applications," J. of Heat Transfer, Vol. 86(C), pp. 373-382. https://doi.org/10.1115/1.3688700
  9. Beck, J. V., 1970, "Nonlinear Estimation Applied to the Nonlinear Inverse Heat Conduction Problem," Int. J. Heat & Mass Transfer, Vol. 13, pp. 703-716. https://doi.org/10.1016/0017-9310(70)90044-X
  10. Kim, Y. C., Nishio, S. and Ohkubo, H., 1995, "Spray Cooling with Formation of Liquid Film (Distribution of Heat Transfer Coefficient in High Temperature Region)," Trans. of the JSME(B), Vol. 60-574, pp. 2158-2164.
  11. Kim, Y. C. and Yun, S. M., 2006, "Study on Film Boiling Heat Transfer of Spray Cooling in Air-Water Full Cone Spray System," Trans. Korean Soc. Mech. Eng. B, Vol. 30, No. 12, pp. 1236-1242. https://doi.org/10.3795/KSME-B.2006.30.12.1236
  12. Kim, Y. C. and Yun, S. M., 2007, "Study on Correlation of Droplet Flow rate and Film Boiling Heat Transfer in Spray Cooling," Trans. Korean Soc. Mech. Eng. B, Vol. 31, No. 4, pp. 335-340. https://doi.org/10.3795/KSME-B.2007.31.4.335
  13. Holman, J. P., 2001, Experimental Methods for Engineers (7thed.), McGraw-Hill, pp. 51-60.