粒度分布具有分形特征的非均匀颗粒流的有效热导率理论研究

根据稠密气体运动学理论，在近平衡条件下，得到粒度分布具有分形特征的非均匀颗粒流系统的速度几率分布函数．研究了低浓度的非均匀颗粒流中颗粒与流体之间因颗粒的随机运动而产生的有效热传导；理论推导了其有效热导率；讨论了系统各参数对有效热导率的影响；并将研究结果与单一颗粒流和两组分的混合颗粒流的有效热导率理论结果进行了比较，结果表明，本文的理论结果更具有一般性、包含了已有的理论结果．

Theoretical Study on the Effective Thermal Conductivity of a Non-uniform Granular Flow with the Fractal Characteristic of Particle Size Distribution

Based on the dense-gas kinetic theory,under the condition of quasi-equilibrium,we bring forward the velocity probability distribution function of non-uniform granular flow with the fractal characteristic of the particle size distribution.We investigate the thermal conductivity in the granular flow due to the movement of the particles,namely the heat transfer induced by the streaming mode only.The effective thermal conductivity is theoretically derived,and the influences of the system parameters such as the structural character parameter,solid fraction and fractal dimension of the particle size distribution on the thermal conductivity are discussed.Comparing our conclusions with the theoretical results of simple and binary mixture of granular flow,we found that our results contain the theoretical data.