Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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On Compositional Convection in Near-Eutectic Solidification System Cooled from a Bottom Boundary

  • Hwang, In Gook (Department of Chemical Engineering, The University of Suwon)
  • Received : 2016.06.20
  • Accepted : 2016.08.24
  • Published : 2017.12.01
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Abstract

Natural convection is driven by the compositional buoyancy in solidification of a binary melt. The stabilities of convection in a growing mushy layer were analyzed here in the time-dependent solidification system of a near-eutectic melt cooled impulsively from below. The linear stability equations were transformed to self-similar forms by using the depth of the mushy layer as a length scale. In the liquid layer the stability equations are based on the propagation theory and the thermal buoyancy is neglected. The critical Rayleigh number for the mushy layer increases with decreasing the Stefan number and the Prandtl number. The critical conditions for solidification of aqueous ammonium chloride solution are discussed and compared with the results of the previous model for the liquid layer.

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References

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