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

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Experimental Study on Heat Flux Partitioning in Subcooled Nucleate Boiling on Vertical Wall

수직 벽면에서 과냉 핵비등 시 열유속 분배에 관한 실험적 연구

  • 송준규 (경희대학교 원자력공학과) ;
  • 박준석 (경희대학교 원자력공학과) ;
  • 정샛별 (경희대학교 원자력공학과) ;
  • 김형대 (경희대학교 원자력공학과)
  • Received : 2013.12.01
  • Accepted : 2014.03.05
  • Published : 2014.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

To validate the accuracy of the boiling heat flux partitioning model, an experiment was performed to investigate how the wall heat flux is divided into the three heat transfer modes of evaporation, quenching, and single-phase convection during subcooled nucleate boiling on a vertical wall. For the experimental partitioning of the wall heat flux, the wall heat flux and liquid-vapor distributions were simultaneously obtained using synchronized infrared thermometry and the total reflection technique. Boiling experiments of water with subcooling of $10^{\circ}C$ were conducted under atmospheric pressure, and the results obtained at the wall superheat of $12^{\circ}C$ and average heat flux of $283kW/m^2$were analyzed. There was a large difference in the heat flux partitioning results between the experiment and correlation, and the bubble departure diameter and bubble influence factor, which account for a portion of the surrounding superheated liquid layer detached by the departure of a bubble, were found to be important fundamental boiling parameters.

본 연구에서는 비등 열유속 분배 모델의 예측 정확성을 검증하기 위하여 수직평판 자연대류 과냉 비등에서 기화, 급랭, 및 단상대류 열전달 기구에 대한 열유속 분배 특성을 실험적으로 조사하였다. 비등 열유속의 분배를 위해 적외선 열화상 기법과 전반사 가시화 기법을 동기화하여 비등 표면의 열유속 분포와 액상-기상 분포를 동시에 측정하여 분석하는 실험을 수행하였다. 실험은 대기압 조건에서 과냉도 $10^{\circ}C$를 가지는 물을 이용하여 수행하였으며, 벽면과열도 $12^{\circ}C$ 및 평균 열유속 $283kW/m^2$ 조건에 대한 실험 결과를 분석에 활용하였다. 실험을 통해 획득된 열유속 분배 결과는 상관식을 이용한 예측 결과와 큰 차이를 보였으며, 기포이탈직경과 기포이탈 시 주변의 과열액체층이 함께 뜯겨져 나가는 효과를 고려한 기포영향인자가 차이를 만드는 주요 원인들로 파악되었다.

Keywords

References

  1. In, W. K., Shin, C. H., Oh, D. S. and Chun, T. H., 2004, "Numerical Analysis of the Subcooled Boiling Flow in a Heated Rod Bundle," The Third National Congress on Fluids Engineering, August 26-28, Jeju, Korea.
  2. Jo, J. C., Kim, H. J., Kim, W. S., Yu, S. O. and Lee, Y. K., 2004, "Numerical Analysis of Boiling-induced Multiphase Flow in a Helical Steam Generator Coiled Tube," The Third National Congress on Fluid Engineering, August 26-28, Jeju, Korea.
  3. Son, G., 2001, "Numerical Simulation of Bubble Motion During Nucleate Boiling," Trans. Korean Soc. Mech. Eng. B, Vol. 25, No. 3, pp. 389-396.
  4. Kurul, N. and Podowski, M. Z., 1990, "Multidimensional Effects in Forced Convection Subcooled Boiling," Proceedings of the 9th Int. Heat Transfer Conference, Vol 2, pp. 19-24.
  5. ANSYS Inc., 2010, ANSYS Fluent Theory 13.0 Guide Manual, USA.
  6. AEA Technology, 1997, CFX-4 Solver Manual, Harwell, UK.
  7. Bjorg, R. W., Hall, G. R. and Rohsenow, W. M., 1982, "Correlation of Forced Convection Boiling Heat Transfer Data," Int. J. Heat Mass Transfer, Vol. 25, No. 6, pp. 753-757. https://doi.org/10.1016/0017-9310(82)90087-4
  8. Kandlikar, S. G., 1998, "Heat Transfer Characteristics in Partial Boiling, Fully Developed Boiling, and Significant Void Flow Regions of Subcooled Flow Boiling," J. Heat Transfer, Vol. 120, No. 2, pp. 395-401. https://doi.org/10.1115/1.2824263
  9. Lahey, R. T., 1978, "A Mechanistic Subcooled Boiling Model," Proceedings of the 6th Int. Heat Transfer Conference, Vol. 1, pp. 293-297.
  10. Basu, N., Warrier, G. R. and Dhir, V. K., 2005, "Wall Heat Flux Partitioning During Subcooled Flow Boiling: Part II - Model Validation," J. Heat Transfer, Vol 127, pp. 141-148. https://doi.org/10.1115/1.1842785
  11. Nishio, S., Gotoh, T. and Nagai, N., 1998, " Observation of Boiling Structures in High Heat-flux Boiling," Int. J. Heat and Mass Transfer, Vol. 41, No. 21, pp. 3191-3201. https://doi.org/10.1016/S0017-9310(98)00062-3
  12. Gerardi, C. D., 2009, "Investigation of the Pool Boiling Heat Transfer Enhancement of Nano Engineered Fluids by Means of High-speed Infrared Thermography," Ph.D. thesis, Massachusetts Institute of Technology.
  13. Chung, H. J. and No, H. C., 2003, "Simultaneous Visualization of Dry Spots and Bubbles for Pool Boiling of R-113 on a Horizontal Heater," Int. J. Heat and Mass Transfer, Vol. 46, No. 12, pp. 2239-2251. https://doi.org/10.1016/S0017-9310(02)00524-0

Cited by

  1. The Effect of Impact Velocity on Droplet-wall Collision Heat Transfer Above the Leidenfrost Point Temperature vol.39, pp.7, 2015, https://doi.org/10.3795/KSME-B.2015.39.7.567
  2. Numerical Study of Low-pressure Subcooled Flow Boiling in Vertical Channels Using the Heat Partitioning Model vol.40, pp.7, 2016, https://doi.org/10.3795/KSME-B.2016.40.7.457