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MULTIPLE SOLUTIONS IN NATURAL CONVECTION BETWEEN TWO HORIZONTAL PLATES WITH SMALL MAGNITUDE NON-UNIFORM TEMPERATURE IN THE UPPER PLATE

위 평판이 작은 불균일 온도를 갖는 두 수평 평판 사이의 자연 대류에서의 다중해

  • Yoo, Joo-Sik (Dept. of Mechanical Engineering Education, Andong Nat'l Univ.)
  • 유주식 (안동대학교 기계교육과)
  • Received : 2016.06.29
  • Accepted : 2016.07.12
  • Published : 2016.09.30

Abstract

Multiple solutions in natural convection of water with Pr=7 between two horizontal plates with small magnitude non-uniform temperature distribution in the upper plate is numerically investigated. The dimensionless temperature of upper plate is ${\theta}={\epsilon}sinkx$. Two upright cells are formed over one wave length in the conduction-dominated regime of small Rayleigh number. However, multicellular convection occurs above a critical Rayleigh number for small wave number. When k = 1.5, dual solutions are found and a transition of $6{\rightarrow}4$ eddy flow occurs with decrease of Rayleigh number. When k = 0.75, two, three, four and five multiple solutions are observed. Transitions of $14{\rightarrow}12$, $12{\rightarrow}10$, $10{\rightarrow}8$ and $6{\rightarrow}8$ eddy flow occur with decrease of Rayleigh number.

Keywords

References

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