人工制备生物消光材料空气动力学特性

人工制备的几种生物材料生产成本低、密度小、形态可控、安全环保，在可见光和红外等波段具有较好的消光能力，可作为一种新型消光材料，弥补无机消光材料的不足。针对当前军、民用领域对新型生物消光材料的需求，将生物消光材料中的絮状生物颗粒等效为子弹玫瑰花型粒子，根据牛顿第二定律和梯度-输运理论，建立生物消光材料沉降模型和扩散模型，并讨论絮状生物颗粒结构和风速、大气稳定度对生物消光材料空气动力学特性的影响。结果表明:分枝数目、长度、半径决定絮状生物颗粒结构；在某种特定条件下，絮状生物颗粒沉降速度较等体积球颗粒沉降速度降低了50％；烟团遮蔽面积可达20 m2以上。模型的构建将为生物消光材料发展及实际应用提供理论基础。

Aerodynamic property of artificial biological extinction material

Several kinds of artificial biological materials have the characteristics of low production cost, low mass density, controllable morphology, safety and environmental friendliness, and better extinction ability in the visible and infrared bands, which can be used as new extinction materials to make up for the shortage of inorganic extinction materials. With the increasing demands for new biological extinction materials in military and civilian fields, the flocculent biological particles in the biological extinction material are equivalent to bullet rosette particles. According to Newton's second law and gradient transport theory, the sedimentation and diffusion models of biological extinction material were established. The structures of flocculent biological particles and wind speed and atmospheric stability' influences on aerodynamic characteristics of biological extinction materials were discussed. The results indicate that the structures of flocculent biological particles are controlled by the number of branches, as well as their length and radius. Under given conditions, the settling rate of flocculent biological particle decreased by 50% compared with that of equal volume sphere particle. And the max covering area of smoke can reach more than 20 m2. The model provides a theoretical basis for the further development and use of biological extinction materials.