Conjugate Heat Transfer in Cylindrical Annulus for an Insulated Tube

단열관을 위한 원통 환상공간 내에서의 복합 열전달

  • 강병희 (동아대학교 대학원 기계공학과) ;
  • 양성환 (마산전문대학 자동차과) ;
  • 권순석 (동아대학교 기계공학과)
  • Published : 1995.11.01

Abstract

The effect of the gap width on conjugate heat transfer in the cylindrical annulus for an insulated tube has been studied numerically by the finite difference method. The parameters considered here are the Rayleigh number, Ra, the dimensionless insulated wall thickness, $W/D_i$ and the dimensionless gap width, S/W. As S/W increases, the mean wall temperature increases at the inside wall of annulus and decreases at the outside walls of annulus and the insulated tube at $S/W{\leq}0.5$, and then slightly increases at $Re=10^4$, $W/D_i=1.47$. The heat transfer rate decreases at $S/W{\leq}0.5$ and then increases apparently as S/W increases at $Re=10^4$, W/Df=1.47. Therefore, it is considered that $$S/W{\sim_=}0.5$$ is the optimum gap width for the effect of insulation at $Re=10^4$, $W/D_f=1.47$.

Keywords