【摘要】 对激光作用下Rayleigh粒子射流的动态汇聚和流动稳定性进行了研究.激光技术在微纳尺度微粒操作方面应用广泛,如光镊.而激光对颗粒群体作用的研究则主要集中在对颗粒群体行为特征的光学映射和测量,对激光影响颗粒群体动力学行为的研究还比较鲜见.基于颗粒动力学模拟及流动稳定性理论分析,考察了稀薄射流(点源)与颗粒射流2种情况.对于点源模拟,通过与经典真空蒸镀沉积理论对比发现,激光对于稀薄颗粒气体的运动确实进行了有效的诱导,使得颗粒在空间的分布更为集中;对于纳米颗粒射流,模拟和理论分析同时表明,光场力会抑制颗粒射流界面长波与短波的失稳,具有广谱致稳特征,可以有效地对颗粒射流进行收束.更多还原

【Abstract】 Dynamic convergence and stability characteristics of Rayleigh particle jets under laser irradiation are studied. Laser technology has widely applications in particle operation at micro-nano scales such as optical tweezers. While researches of particle behavior under laser irradiation generally focus on optical mapping and measurement of the particle population characteristics, laser-induced particle dynamical behaviors are rarely studied.Based on the analysis of granular gas dynamic simulation and the flow instability theory,the two cases of rarefied granular jet(point source) and granular jet are investigated. For point sources, that laser is effective in making the particle distribution more concentrated in the space by comparing with the classical vacuum deposition theory is found. In the case of granular jet, simulation and theoretical analysis show that the light scattering force can suppress instability of the long and short wavelengths, and effectively gather nanoparticles into jet.更多还原