喷嘴结构及工艺参数对固体推进剂3D打印挤出成型的影响分析

Analysis of nozzle structure and process parameters on 3D printing extrusion forming of solid propellant

为研究喷嘴结构及工艺参数对固体推进剂3D打印挤出的影响规律,从而更好地指导喷嘴结构优化与挤出工艺改进,实现高质量连续的固体推进剂挤出与成型,以某固体推进剂3D打印机喷嘴结构为例,开展了固体推进剂3D打印挤出过程的有限元分析,确定了喷嘴直径、喷嘴收缩角、工艺温度和壁面滑移系数四个因素为设计参数,以出口速度均匀性指数与压力降为目标结果,对固体推进剂3D打印挤出工艺进行了正交试验设计,并利用灰色关联度分析法和极差分析法对试验结果进行多目标优化处理。结果表明,相比于其他因素壁面滑移系数对优化目标的影响程度最大,并且当喷嘴直径为1.5 mm、喷嘴收缩角为120°、工艺温度为60℃、壁面滑移系数为103时推进剂药料的挤出成型性能最优,此时的灰色关联度值为0.8018。

In order to further study the influence of nozzle structure and process parameters on the 3D printing extrusion process of solid propellant,so as to better guide the nozzle structure optimization and extrusion process improvement,to achieve high-quality continuous solid propellant extrusion and molding requirements,in this study,taking the nozzle structure of a solid propellant 3D printer as an example,the finite element analysis of the extrusion process of solid propellant 3D printing was carried out,and the four factors of nozzle diameter,nozzle shrinkage angle,process temperature and wall slip coefficient were determined as design parameters,with outlet velocity uniformity index and pressure drop as the target results,an orthogonal experimental design was carried out on the solid propellant 3D printing extrusion process.Multi-objective optimization of the test results was performed using the gray correlation analysis method and the range analysis method.The results indicate that among all the factors,the wall slip coefficient has the most significant influence on the optimization objective.The optimum conditions for the extrusion molding performance of the propellant material are found to be a nozzle diameter of 1.5 mm,a nozzle shrinkage angle of 120°,a process temperature of 60℃,and a wall slip coefficient of 103,resulting in a gray correlation value of 0.8018.