한국전산유체공학회지 (Journal of computational fluids engineering)

한국전산유체공학회 (Korean Society of Computational Fluids Engineering)
권호 표지

벽 비등모델을 이용한 과냉비등 유동에 대한 CFD 모의계산에서 벽 인접격자의 영향

NEAR-WALL GRID DEPENDENCY OF CFD SIMULATION FOR A SUBCOOLED BOILING FLOW USING WALL BOILING MODEL

  • 투고 : 2010.06.08
  • 심사 : 2010.09.10
  • 발행 : 2010.09.30
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

boiling flow in vertical tube. The multiphase flow model used in this CFD analysis is the two-fluid model in which liquid(water) and gas(vapour) are considered as continuous and dispersed fluids, respectively. A wall boiling model is also used to simulate the subcooled boiling heat transfer at the heated wall boundary. The diameter and heated length of tube are 0.0154 m and 2 m, respectively. The system pressure in tube is 4.5 MPa and the inlet subcooling is 60 K. The near-wall grid size in the non-dimensional wall unit for lqiuid phase ($y^+_{w,l}$) was examined from 101 to 313 at the outlet boundary. The CFD calculations predicted the void distributions as well as the liquid and wall temperatures in tube. The predicted axial variations of the void fraction and the wall temperature are compared with the measured ones. The CFD prediction of the wall temperature is shown to slightly depend on the near-wall grid size but the axial void prediction has somewhat large dependency. The CFD prediction was found to show a better agreement with the measured one for the large near-wall grid, e.g., $y^+_{w,l}$ > 300 at the tube exit.

키워드

참고문헌

  1. 1975, Ishii, M., Thermo-Fluid Dynamic Theory of Two-Phase Flow, Eyrolles.
  2. 1990, Lahey, R.T. and Drew, D., "The Current State-of-the-Art in the Modeling of Vapor/Liquid Two-Phase Flow," ASME Reprint, 90-WA/HT-13.
  3. 1994, Bertodano, M.L., Lahey, R.T.Jr. and Jones, O.C.Jr., "Development of a Model for Bubbly Two-Phase Flow," J. Fluids Engineering, Vol.116, pp.128-134. https://doi.org/10.1115/1.2910220
  4. 1981, Sato, Y., Sadatomi, M. and Sekoguchi, K., "Momentum and Heat Transfer in Two-Phase Bubbly Flow - I," Int. J. Multiphase Flow, Vol.7, pp.167-177. https://doi.org/10.1016/0301-9322(81)90003-3
  5. 1990, Kurul, M., "Multidimensional Effects in Two-Phase Flow including Phase Change," Ph.D. Thesis, Rensselaer Polytechnic Institute.
  6. 1993, Anglart, H., "Modelling of Vapor Generation Rate at Wall in Subcooled Boiling Two-Phase Flow," First CFDS International User Conference, Oxford, UK, pp.183-207.
  7. 1997, AEA Technology, CFX-4.2: Solver, Oxfordshire UK.
  8. 1967, Bartolomei. and Chanturiya, V.M., "Experimental Study of True Void Fraction When Boiling Subcooled Water in Vertical Tubes," Thermal Engineering, Vol.114, pp.123-128.
  9. 1996, Anglart, H. and Nylund, O., "CFDS Application to Prediction of Void Distribution in Two-Phase Bubbly Flows in Rod Bundles," Nucl. Sci. Eng., Vol.163, pp.81-99. https://doi.org/10.1016/0029-5493(95)01160-9
  10. 2003, Krepper, E., "CFD Modeling of Subcooled Boiling," The 10th Int. Topical Meeting on Nuclear Reactor Thermal hydraulics (NURETH-10), Seoul, Korea, October 5-9.
  11. 1952, Ranz, W.E. and Marshall, W.R., "Evaporation from Drops," Chemical Engineering Progress, Vol.48, pp.141-148.