Large Eddy Simulation of a Planar Jet Flow with Nanoparticle Coagulation
Large Eddy Simulation of a Planar Jet Flow with Nanoparticle Coagulation
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DOI：
10.1007/s10409-006-0011-z
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发表时间：
2006-05
影响因子：
3.5
通讯作者：
Mingzhou Yu;Jianzhong Lin;Lihua Chen;T. Chan
中科院分区：
文献类型：
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作者：
Mingzhou Yu;Jianzhong Lin;Lihua Chen;T. Chan
用大涡模拟方法研究了平面射流中纳米颗粒在大共格结构下的凝聚与生长。用矩量法逼近纳米粒子的一般动力学方程，得到粒子场。含有直径为1纳米的颗粒的不可压缩流体被投射到无颗粒的环境中。结果表明，随着射流的发展，纳米粒子的数量、强度、直径和多分散性分布的演化主要由共格结构决定。此外，共格结构增加了颗粒的扩散，涡旋卷起使颗粒分布更加不规则，而涡对使颗粒分布变得均匀。当射流向下游流动时，射流核心的时均颗粒数浓度变低，外围时均颗粒数浓度增大，而整个流场的时均颗粒质量保持不变，时均颗粒直径和几何标准差在射流区域与周围环境交界处增大并达到最大值。
Coagulation and growth of nanoparticles subject to large coherent structures in a planar jet has been explored by using large eddy simulation. The particle field is obtained by employing a moment method to approximate the nanoparticle general dynamic equation. An incompressible fluid containing particles of 1 nm in diameter is projected into a particle-free ambient. The results show that the coherent structures dominate the evolution of the nanoparticle number intensity diameter and polydispersity distributions as the jet develops. In addition, the coherent structures act to increase the diffusion of particles, and the vortex rolling-up makes the particles distributing more irregularly while the vortex pairing causes particle distributions to become uniform. As the jet travels downstream, the time-averaged particle number concentration becomes lower in the jet core and higher in the outskirts, whereas the time-averaged particle mass over the entire flow field maintains unaltered, and the time-averaged particle diameter and geometric standard deviations grow and reach their maximum on the interface of the jet region and the ambient.