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arXiv · 2311.11244

Micromechanical Origin of Heat Transfer to Granular Flow

Xintong Zhang·Sarath Adapa·Tianshi Feng·Jian Zeng·Ka Man Chung·Clifford Ho·Kevin Albrecht·Renkun Chen
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Abstract

Heat transfer to a granular flow is comprised of two resistances in series: near the wall and within the bulk particle bed, neither of which is well understood due to the lack of experimental probes to separate their respective contribution. Here, we use a frequency modulated photothermal technique to separately quantify the thermal resistances in the near-wall and the bulk bed regions of particles in flowing states. Compared to the stationary state, the flowing leads to a higher near-wall resistance and a lower thermal conductivity of bulk beds. Coupled with discrete element method simulation, we show that the near-wall resistance can be explained by particle diffusion in granular flows.

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Xintong Zhang, Sarath Adapa, Tianshi Feng, Jian Zeng, Ka Man Chung, Clifford Ho, Kevin Albrecht, Renkun Chen. 2023-11-19. Micromechanical Origin of Heat Transfer to Granular Flow. https://arxiv.org/abs/2311.11244

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