铝粉粒度和含量对NEPE推进剂燃烧产物颗粒阻尼的影响

Effects of Particle Size and Content of Al Powders on the Particle Damping of Combustion Products of NEPE Propellant

为研究铝粉粒度和含量对NEPE推进剂燃烧产物颗粒阻尼的影响,采用密闭弹燃烧法收集了NEPE推进剂的凝相燃烧产物并开展粒度分析,根据Culick线性颗粒阻尼理论计算了燃烧产物对声不稳定燃烧的颗粒阻尼。结果表明,铝粉的粒度和含量均显著影响NEPE推进剂燃烧产物对声不稳定燃烧的颗粒阻尼,主要是由于铝粉粒度和含量影响了凝相燃烧产物的粒度分布。对一定频率声不稳定燃烧,凝相燃烧产物中粒径处于[1/2D_(opt),2D_(opt)](D_(opt)为最佳颗粒粒径)区间的颗粒质量分数越高,燃烧产物的颗粒阻尼效率系数越大,产生的颗粒阻尼越大。燃烧产物中凝相燃烧产物的质量分数是决定颗粒阻尼大小的因素之一,与推进剂中铝粉含量呈正相关。

To study the effects of particle size and content of Al powders on the particle damping generated by nitrate ester plasticized polyether（NEPE） propellant combustion products,the condensed phase combustion products of NEPE propellant were collected by a sealed bomb method and the particle size analysis was performed. The particle damping of combustion products on acoustic instability was calculated according to the theory of Culick linear particle damping. Results show that the particle size and content of Al powders significantly affect the particle damping of NEPE propellant combustion products on acoustic instability combustion,which mainly is due to the particle size and content of Al powders affect the particle size distribution of condensed phase combustion products. For a certain frequency acoustic instability combustion,the higher the mass fraction of particle in [1/2Dopt,2Dopt]particle size interval in the condensed phase combustion products is,the greater the efficiency coefficient of particle damping of combustion products is,the larger the produced particle damping is. The mass fraction of condensed phase combustion products in combustion products is one of the factors determining the scale of particle damping,and which is positively correlated with the content of Al powders in propellant.