固体火箭发动机喷管化学烧蚀的动态数值模拟  

Dynamic Numerical Simulation of Chemical Erosion in Solid Rocket Motor Nozzle

作　　者：于勇[1] 张航维 YU Yong;ZHANG Hangwei(School of Aerospace Engineering,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学宇航学院,北京100081

出　　处：《北京理工大学学报》2023年第7期693-701,共9页Transactions of Beijing Institute of Technology

摘　　要：为分析固体火箭发动机喷管的化学烧蚀过程,准确预测喷管壁面烧蚀率,在Fluent平台上采用UDF二次开发方法,结合壁面化学反应模型和动网格技术建立了动态烧蚀模型,实现了喷管型面衰退和内流场变化的双向耦合作用.针对推进剂中不同Al质量分数的工况,利用动态烧蚀模型对70-lb BATES发动机喷管的二维非定常流固热耦合过程进行了数值仿真计算,论证了模型的准确性.结果表明:烧蚀率计算值与试验值基本一致;烧蚀率随推进剂中Al质量分数的增加而降低;动态烧蚀模型能更准确地预测喷管壁面烧蚀率;型面衰退改变了喷管流场,在喉部附近产生了更高的压强和温度;采用动态烧蚀模型计算的喷管在喉部壁面附近的H_(2)O和CO_(2)的浓度更高.To predict nozzle erosion rate and study the chemical erosion in solid rocket motor nozzle,a dynamic erosion model was established by the chemical reaction and dynamic mesh,combined with secondary development on Fluent platform by UDF,and the two-way coupling effect of wall retrogression and internal flow field change of nozzle was realized.Under different propellant aluminum mass fractions,the dynamic erosion model was used to simulate the two dimensional unsteady fluid-solid-thermal coupling process of 70-lb BATES motor nozzle.The results show that,the calculated erosion rates are consistent with experimental data.The erosion rate decreases with the increase of aluminum mass fraction.The dynamic erosion model can predict nozzle erosion rate more accurately.The wall retrogression of nozzle surface changes the flow field and produces higher pressure and temperature near the throat.The concentrations of H_(2)O and CO_(2)near the throat calculated by the dynamic erosion model are higher.

关 键 词：数值模拟 喷管 化学烧蚀 流固耦合 

分 类 号：V435.14[航空宇航科学与技术—航空宇航推进理论与工程]