Numerical Study of Unsteady Mixed Convection in a Cavity with High Viscous Fluid

캐비티 내 고 점성유체의 비정상 흔합대류에 관한 수치해석적 연구

  • 배대석 (부경대학교 기계공학부) ;
  • Published : 2009.10.31


A numerical study of unsteady mixed convection in a cavity with high viscous fluid is presented. Finite volume method was employed for the discretization and PISO algorithm was used for calculating pressure term. The parameters governing the problem are the Rayleigh number ($10^3\;{\leq}\;Ra\;{\leq}\;10^5$), the Reynolds number (0 < Re $\leq$ 1), and the aspect ratio (0.5 $\leq$ AR $\leq$ 2). The fluid used is silicon oil, a high prandtl number fluid, Pr = 909.1. The results show velocity vectors and temperature distributions. It is found that the periodic flows in a cavity are observed at very low Reynolds numbers, and the period of periodic flow decreases with increasing Reynolds and Rayleigh numbers, and increases with increasing aspect ratio. Also, the Reynolds number range of periodic flow increases with increasing Rayleigh numbers and aspect ratio.


  1. A. Amahmid., M. Hasnaoui and P. Vass- eur, 1997, "Multiplicite des solutions en convection naturelle dans une geometrie repetitive", Int. J. Heat Mass Transfer, Vol. 40, pp. 3805-3818.
  2. M. Hasnaoui., E. Bilgen and P. Vasseur, 1996, "Natural convection above an Array of open cavities heated from below", Numerical Heat Transfer, Part A, Vol. 18, pp. 463 - 482.
  3. W. Aung, 1983, "An Inteferometric Investigation of Separated Forced Convection in Laminar Flow Past Cavities", accepted for publication in ASME J. Heat Transfer, Vol. 105, Aug. pp. 505-512.
  4. T. J. Yong and K. Vafai, 1998, "Convective cooling of a heated obstacle in a channel", Int. J. Heat Mass Transfer, Vol. 41, pp. 3131-3148.
  5. T. J. Yong and K. Vafai, 1998, "Convective flow and heat transfer in a channel containing multiple heated obstacle", Int. J. Heat Mass Transfer, Vol. 41, pp. 3279-3298.
  6. C. Herman and E. Kang, 2001, "Experimental visualisation of temperature fields and study of heat transfer enhancement in oscillatory flow in a grooved channel", Heat Mass Transfer, Vol. 37, pp. 87-99.
  7. M. E. Braaten and S.V. Patankar, 1985, "Analysis of laminar mixed convection in shrouded arrays of heated rectangular blocks", Int. J. Heat Mass Transfer, Vol. 28, pp. 1699-1709.
  8. H. W. Wu and S. W. Pemg, 1998, "Heat transfer augmentation of mixed convection through vertex shedding from an inclined plate in a vertical channel containing heated blocks", Num. Heat Transfer, Part A, Vol. 33, pp. 225-244.
  9. M. Hasnaoui et al., 1991, "Mixed conv- ective heat transfer in a horizontal channel heated periodically from below", Num. Heat Transfer, Part A, Vol. 20, pp. 297 - 315.
  10. M. Najam, A. Amahmid, M. Hasnaoui and M. EiAlami, 2003, "Unsteady mixed convection in a horizontal channel with rectangular blocks periodically distributed on its lower well", Int. J. Heat and Fluid flow, Vol. 24, pp. 726-735.