纳米颗粒形状、尺寸、含量及颗粒级配对炸药悬浮液粘度影响的DPD模拟

采用耗散粒子动力学(DPD)模拟技术研究了纳米颗粒形状、尺寸、含量以及颗粒级配等因素对悬浮液体系粘度的影响。模拟结果显示,在纳米颗粒低含量情况下,纳米颗粒形状的影响基本可以忽略。随着纳米颗粒含量增加,悬浮液粘度也会随之上升;对于相同含量的纳米颗粒而言,尺寸越小,悬浮液粘度越大;添加纳米颗粒的行为不会改变基液粘度与温度之间的依赖关系;含量相同情况下,两种不同尺寸的纳米颗粒进行颗粒级配可以有效调整体系粘度。通过引入纳米颗粒溶剂化效应修正了传统的爱因斯坦粘度公式,将颗粒尺寸与含量的影响归于一个模型之中。该模型的修正使爱因斯坦粘度公式可以有效预测从纳米尺度到微米尺度的悬浮液粘度。

DPD Simulations on the Effect of Nanoparticle Shapes, Sizes, Contents and Gradations on the Viscosity of Energetic Suspensions

Controlling the fluid behaviors of energetic suspensions is one of the crucial technologies for controlling the inner defects of munitions. Considering the lack work on energetic suspensions with nanoparticles, dissipative particle dynamics(DPD) simulation technology was used to investigate the influences of particle shape, size, content and gradation on the viscosity of energetic suspension systems in this paper. It shows that the influence of the particle shape can be neglected in the case of low contents. With the increase of the content of nanoparticles, the viscosity of the suspension rises accordingly. For a same amount of nanoparticles, the smaller the size, the greater the viscosity of the suspension. The addition of nanoparticles does not change the dependence of the system viscosity on the temperature. For the same content, the particle gradation of two different sizes of nanoparticles can effectively adjust the viscosity of the system. By introducing the solvation effect of nanoparticles, the traditional Einstein viscosity calculation formula is corrected to be more efficient. The particle size and content are both introduced to a model to effectively predict the viscosity of fluids ranging from nano- to micro-scale.