摘要
从不同层次上研究了循环流化床颗粒相的湍流结构。ＰＤＡ测量发现颗粒在壁面附近的运动表现出显著的成团特征和湍流度显著降低，小波分析法得到的直观图形象地揭示了颗粒速度脉动的自相似、分叉等具有混沌特征的微观结构，且在不同的尺度上颗粒速度脉动表现出各向异性的特征。
Turbulence structures of solid phase in a circulating fluidized bed were (CFB) characterized. The investigations were carried out using a Particle Dynamic Analyzer (PDA). Temporal evolutions of the particle velocity fluctuation indicate that the great agitation and non-homogeneity with time and space coordinate of the solid phase. The studies on turbulent density illustrate that the turbulence in the CFB is an anisotropic turbulence, and the particle turbulent density decreased sharply as the measurement points move away from the wall. To further understand the microstructure of the particle velocity fluctuation, wavelet analysis was also adopted. The vivid imagines show that it is an anisotropic turbulence at all scales and its fractal and dissipative structure.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2001年第1期119-122,共4页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目!(No.59876014)
关键词
气固流化床
湍流结构
循环流化床
燃煤锅炉
gas-solid fluidized beds
wavelet transform
turbulence structure
particle dynamic analyzer
