Heat transfer characteristics of a fractal particle in a low Reynolds number flow

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Abstract

Current heat transfer coefficient formulae for particles are derived from data for spheres. However, a real particle is not a sphere, but an irregular body, so the assumption that the real particle approximates a sphere is questionable in mathematical models. Fractal models, which give shapes similar to real particles, are produced by the random walk method to calculate the heat transfer coefficient of a factual particle in a low Reynolds number flow using kinetic theory and gas diffusion theory. The particle diameter is less than 5 μm. Simulations show that the spherical assumption is not suitable for the fractal particle with a maximum error of 82%. Nu is then greatly influenced by the specific area and fractal dimension.

Keywords fractal particle kinetic theory molecular diffusion heat transfer coefficient

Issue Date: 15 June 2014

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	Junwu YU
	Rong HE
	Yanguo ZHANG

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Junwu YU,Rong HE,Yanguo ZHANG. Heat transfer characteristics of a fractal particle in a low Reynolds number flow[J]. Journal of Tsinghua University(Science and Technology), 2014, 54(6): 781-786.

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http://jst.tsinghuajournals.com/EN/ OR http://jst.tsinghuajournals.com/EN/Y2014/V54/I6/781

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