화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
Korean Journal of Chemical Engineering, Vol.21, No.1, 69-74, January, 2004
DOI10.1007/BF02705382  Export Citation
Onset of Buoyancy-Driven Convection in the Horizontal Fluid Layer Heated from Below with Time-Dependent Manner
Min Chan Kim†, Tae Joon Chung1, and Chang Kyun Choi1
  • Department of Chemical Engineering, Cheju National University, Cheju 690-756, Korea
  • 1School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea
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The onset of buoyancy-driven convection in an initially isothermal, quiescent fluid layer heated from below with time-dependent manner is analyzed by using propagation theory. Here the dimensionless critical time τc to mark the onset of convective instability is presented as a function of the Rayleigh number Raφ and the Prandtl number Pr. The present stability analysis predicts that τc decreases with increasing Pr for a given Raφ. The present predictions compare reasonably well with existing experimental results. It is found that in deep-pool systems the deviation of temperature profiles from conduction state occurs starting from a certain time τ=(2~4)τc.
Keywords:Buoyancy-driven Instability;Critical Time;Propagation Theory;Ramp Heating
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