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HEAT TRANSFER CHARACTERISTICS IN A FAST PYROLYSIS REACTOR FOR BIOMASS  

Choi, Hang-Seok (한국기계연구원, 그린환경에너지기계연구본부)
Publication Information
Journal of computational fluids engineering / v.15, no.1, 2010 , pp. 9-16 More about this Journal
Abstract
The characteristics of flow and heat transfer in a bubbling fluidized bed are investigated by means of computational fluid dynamics (CFD). To simulate two-phase flow for the gas and solid flows, Eulerian-Eulerian approach is applied. Attention is paid for a heat transfer from the wall to fluidized bed by bubbling motion of the flow. From the result, it is confirmed that heat transfer is promoted by chaotic bubbling motion of the flow by enhancement of mixing among solid particles. In particular, the vortical flow motion around gas bubble plays an important role for the mixing and consequent heat transfer. Discussion is made for the time and space averaged Nusselt number which shows peculiar characteristics corresponding to different flow regimes.
Keywords
Reactor; Heat Transfer; Fluidized Bed; Two-phase Flow; Mixing;
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