考虑颗粒凝并情况下充分发展圆管湍流场中的纳米颗粒的迁移(英文)

• 作 者: 林建忠 刘淞 陈达良
• 机 构: China Jiliang University,State Key Laboratory of Fluid Power Transmission and Control,Zhejiang Unive
• 出 处: Chinese Journal of Chemical Engineering
• 发表日期: 2012年04期
• 关键词: deviation migration coagulation sized turbulent radial initially sizes 圆管 凝并

Numerical simulations of nanoparticle migration in a fully developed turbulent pipe flow are performed.The evolution of particle number concentration,total particle mass,polydispersity,particle diameter and geometric standard deviation is obtained by using a moment method to approximate the particle general dynamic equation.The effects of Schmidt number and Damkhler number on the evolution of the particle parameters are analyzed.The results show that nanoparticles move to the pipe center.The particle number concentration and total particle mass are distributed non-uniformly along the radial direction.In an initially monodisperse particle field,the particle clusters with various sizes will be produced because of coagulation.As time progresses,the particle cluster diameter grows from an initial value at different rates depending on the radial position.The largest particle clusters are found in the pipe center.The particle cluster number concentration and total particle mass decrease with the increase of Schmidt number in the region near the pipe center,and the particles with lower Schmidt number are of many dif-ferent sizes,i.e.more polydispersity.The particle cluster diameter and geometric standard deviation increase with the increase of Damkhler number at the same radial position.The migration properties for nano-sized particles are different from that for micro-sized particles.

Numerical simulations of nanoparticle migration in a fully developed turbulent pipe flow are performed. The evolution of particle number concentration, total particle mass, polydispersity, particle diameter and geometric standard deviation is obtained by using a moment method to approximate the particle general dynamic equation. effects of Schmidt number and Damkhler number on the evolution of the particle parameters are analyzed. results show that nanoparticles move to the pipe center. The particle number concentration and total particle mass are distributed non-uniformly along the radial direction. an initially monodisperse particle field, the particle clusters with various sizes will be produced because of coagulation. As time progresses, the particle cluster diameter grows from an initial value at different rates depending on the radial position. largest particle clusters are found in the pipe center The particle cluster number concentration and total particle mass decrease w ith the increase of Schmidt number in the region near the pipe center, and the particles with lower Schmidt number are of many dif-ferent sizes, iemore polydispersity. particle particle diameter and geometric standard deviation increase with the increase of Damkhler number at the same radial position. The migration properties for nano-sized particles are from from for micro-sized particles.