非规则颗粒系统辐射特性分析
时间:2020-05-15 20:38 来源:毕业论文 作者:毕业论文 点击:次
| 摘要摘 要 本文采用了时域有限差分（FDTD)的方法，对非规则颗粒系统的辐射特性进行了分析研究。 分别研究形状、 尺度参数和周围介质对单个粒子的吸收因子和散射因子的影响。发现形状不同的粒子，在垂直入射光方向截面积越大，吸收和散射因子越大；粒子尺寸足够小时，由于小尺寸效应，吸收和散射因子出现一个局部峰值；周围介质折射率不同，其吸收散射因子也不同。此外周期排列的银纳米粒子系进行了计算分析，包括粒子系独立散射与非独立散射情况、粒子形状、浓度和粒子系周围介质的改变，分析了其反射率和吸收率的变化规律。结论是非独立散射的吸收能力强于独立散射；粒子系内粒子形状吸收率反射率的影响不是很大；粒子浓度越大，吸收率反射率越大；粒子系所处介质不同，辐射特性也不同；48921 毕业论文关键词 非规则颗粒 时域有限差分法 （FDTD) 吸收因子 散射因子 吸收率 反射率 Title The radiation characteristics of irregular particle analysis AbstractIn this paper, the finite difference time domain (FDTD) method was adopted, theradiation characteristics of irregular particle system analysed and studied.Respectively study the shape and scale parameters and the surrounding medium forsingle particle absorption factor and scattering factor influence. Found thatdifferent shapes of particles, in the direction of the incident light absorptioncross section, the greater the absorb scattering factor is larger; Particle sizeenough hours, due to the small size effect, absorption scattering factor in a localpeak; Around the medium the refractive index is different, its absorptionscattering factor is different also. In addition to an array of silvernanoparticles is calculated analysis, both the independent and the particlescattering independently, particle shape, concentration and particle scatteringis the change of the surrounding media, analyzes the change laws of reflectanceand absorption. Conclusion is independent scattering and absorption ability isstronger than scattering; Particle system in the influence of particle shapeabsorption rate reflectivity is not very big; The bigger the particleconcentration, the greater the absorptivity reflectance; Particle system indifferent medium, different radiation characteristics; Keywords Irregular particle model Finite-difference time-domain(FDTD)Absorption factor Scattering factor Absorptivity Refractivity 目次 1引言1 1.1研究背景及意义1 1.3本文研究内容3 2颗粒辐射特性研究理论方法4 2.1常用的理论方法简介4 2.2时域有限差分方法简介5 2.3本章小结.7 3单个粒子的辐射特性影响因素分析.8 3.1FDTD模型的建立.8 3.2颗粒形状的影响9 3.3颗粒尺度参数的影响12 3.4颗粒周围介质的影响13 3.5本章小结.15 4粒子系的辐射特性影响因素分析.16 4.1FDTD仿真模型的建立16 4.2独立散射与非独立散射粒子系.17 4.3系统内粒子形状的影响.18 4.4系统颗粒周围介质的影响.19 4.5系统颗粒浓度的影响20 4.6本章小结.22 结论23 致谢24
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