同轴数字全息用于铝燃烧颗粒的测量研究

Measurement of Particle Size of Aluminum Combustion inSolid Propellant Using Digital In-line Holography

关键词:  固体推进剂  铝燃烧  同轴数字全息  图像重建  概率密度粒径分布

Key words:  Solid propellant  Aluminum combustion  Digital in-line holography（DIH）  Image reconstruction  Particle distribution function（PDF）

摘要:

为获得三维空间范围内固体推进剂铝颗粒动态燃烧的粒径信息，采用同轴数字全息技术对固体推进剂中铝动态燃烧颗粒粒径分布的测量进行了研究。在常温常压下，采用两种放大倍数（1.1倍和2.7倍）的成像系统对两种推进剂进行了全息测量，分别从两种推进剂铝燃烧颗粒的全息重建图像中提取了所有铝燃烧颗粒的粒径信息，采用Log-Normal多峰拟合方法获得了颗粒粒径分布的详细参数。实验结果表明：在颗粒重建全息图的基础上，采用插值方法极大地提高了颗粒粒径的测量精度，在10μm～200μm内，相对测量误差可降低至0.4%。该方法能够清晰获得10μm～900μm内所有铝燃烧颗粒粒径分布和平均粒径等信息，说明该方法适用于固体推进剂铝颗粒燃烧的精细化测量。

Abstract:

In order to obtain the particle sizes of three-dimensional dynamic combustion of aluminum particles in the solid propellant， a new method used digital in-line holography（DIH） techniques for measuring the size of aluminum particle during solid propellants combustion was studied.Under normal pressure and temperature， two propellants were measured with two magnification times （1.1 times and 2.7 times） DIH system， the particle size information of all aluminum combustion particles was extracted from the holographic reconstructed image， and the detailed parameters of particle size distribution were obtained by Log-Normal multi-peak fitting method. The experimental results show that: Based on the particle reconstruction hologram image， the measurement accuracy of particle size is greatly improved by interpolation method， and the relative measurement error can be reduced to 0.4% in the range of 10μm～200μm. The method can clearly obtain the information such as particle size distribution and average particle size of all the aluminum combustion particles in the range of 10μm～900μm， and it is proved that this method is suitable for refine measurement of the aluminum particles combustion in solid propellant. So， it can provide fine measuring means and important data support for inform aluminum and agglomeration combustion model and evaluate new propellant formulations.