Enhancement of Mass Transfer of an Enclosed Fluid by Time-periodic Thermal Forcing

간헐 열전달을 이용한 밀폐용기내의 물질전달 향상

  • 곽호상 (금오공과대학교 기계공학부)
  • Published : 2002.03.01

Abstract

A numerical investigation is made of unsteady double-diffusive convection of a Boussinesq fluid in a rectangular cavity subject to time-periodic thermal excitations. The fluid is initially stratified between the top endwall of low solute concentration and the bottom endwall of high solute concentration. A time-dependent heat flux varying in a square wave fashion, is applied on one sidewall to induce buoyant convection. The influences of the imposed periodicity on double-diffusive convection are examined. A special concern is on the occurrence of resonance that the fluctuations of flow and attendant heat and mass transfers are mostly amplified at certain eigenmodes of the fluid system. Numerical solutions illustrate that resonant convection results in a conspicuous enhancement of time-mean mass transfer rate.

Keywords

References

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