دانلود گزارش کارورزی و کار آموزی

چکیده : 

To analyze the effects of higher wall roughness on dense particle–laden dispersion behaviors under

reduced gravity environments, a dense gas–particle two-phase second-order-moment turbulent model

are developed. In this model, the wall roughness function and the kinetic theory of granular flows are

coupled and closed. Anisotropy of gas–solid two-phase stresses and the interaction between gas–particle

are fully considered using two-phase Reynolds stress model and the two-phase correlation transport

equation. Numerical simulation test is validated by Sommerfeld and Kussin (2003) experiments data

with higher wall roughness 8.32 lm. Predicted results showed that the particle concentration distribution,

particle fluctuation velocity, particle temperature and particle collision frequency are greatly

affected by higher wall roughness, as well as particle Reynolds stress and interactions between gas

and particle turbulent flows are redistributed. Under microgravity conditions, particle temperature and

collision frequency are greatly less than those of earth and lunar gravity.