Thermal Convection Between Two Horizontal Plates with Small Amplitude Non-Uniform Temperatures

작은 진폭의 불균일 온도를 갖는 두 수평 평판 사이에서의 열 대류

  • Yoo Joo-Sik (Department of Mechanical Engineering Education, Andong National University) ;
  • Kim Yong-Jin (Korea Institute of Machinery & Materials)
  • 유주식 (안동대학교 기계교육과) ;
  • 김용진 (한국기계연구원 환경기계기술연구부)
  • Published : 2004.11.01

Abstract

Thermal convection between two horizontal walls kept at small amplitude nonuniform temperatures of the form, $T_L=T_1+a{\Delta}T$ sin kx and $T_U=T_2+b{\Delta}T\;sin(kx-{\beta})$ with a, $b{\ll}1$, is numerically investigated. When the Rayleigh number is small, an upright cell is formed between two walls at ${\beta}=0$; the cell is tilted at ${\beta}={\pi}/2$, and a flow with two-tier-structure cells occurs at ${\beta}={\pi}$. As the Rayleigh number is increased, Nusselt number increases smoothly for ${\beta}=0\;and\;{\pi}/2$, but increases rather steeply for ${\beta}={\pi}$ near the critical Rayleigh number ($Ra_c=1708$). When the wave number is small (k=0.5), multicellular convection occurs over one wave length, for all phase differences, and multiple solutions are found.

Keywords

References

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