火箭推进

针对等离子体发动机安装结构,研究了静力学和动力学条件约束下结构拓扑优化的设计思路和方法。首先,通过模态仿真分析原结构存在的缺点,寻找结构改进方向; 然后,应用拓扑优化设计方法得到满足设计要求的最佳结构构型; 最后,充分考虑结构装配工艺性要求,采用拓扑优化和尺寸优化相结合的方法得到实用的工程最优方案。对比原结构方案,优化方案质量减轻10.8%。在静承载方面,优化结构最大位移减少61.1%,支撑刚度大幅增强; 最大应力减少1.4%,结构上的应力分布更加均匀,平均应力降低。在动承载方面,优化结构上下偏摆和左右偏摆的振动模态明显改善,结构1～6阶振动频率提升了5%～39.8%; 优化结构在随机振动载荷下的RMS应力值和损伤降低,疲劳寿命显著提升。优化后结构的性能提升验证了设计方法的正确性和有效性。

For the mounting structure of plasma engine, the design idea and method of structural topology optimization under the constraints of static and dynamic conditions are studied. Firstly, the defects of the original structure are analyzed by modal simulation to find the direction of structural improvement. Next, the topology optimization design is applied to obtain the optimal configuration that meets the design requirements. Finally, considering the technological requirements of structural assembly, the practical engineering optimal scheme is obtained by combining topology optimization and size optimization. Compared with the original structure, the mass of the optimized structure is reduced by 10.8%. In terms of static bearing capacity, the maximum displacement of the optimized structure is reduced by 61.1%, and the support stiffness is greatly enhanced. The maximum stress of the structure is reduced by 1.4%, the stress distribution is more uniform, and the average stress is reduced. In terms of dynamic bearing capacity, the vibration modes of the optimized structure with up-down and left-right yaw are significantly improved, and the corresponding frequencies of the 1st to 6th order vibration modes are increased by 5% to 39.8%. The RMS stress value and damage of the optimized structure under random vibration load are reduced, and the fatigue life is significantly improved. The correctness and effectiveness of the design method are verified with the performance improvement of the optimized structure.

引言
1 等离子体发动机原安装结构分析
2 等离子体发动机安装结构拓扑优化
3 结论

图1 等离子发动机安装结构<br/>Fig.1 Mounting structure of plasma engine

图1 等离子发动机安装结构
Fig.1 Mounting structure of plasma engine

表1 加速度载荷
Tab.1 Acceleration load

表2 随机振动试验谱<br/>Tab.2 Test spectrum of random vibration

表2 随机振动试验谱
Tab.2 Test spectrum of random vibration

图2 等离子发动机结构模态振型<br/>Fig.2 Modal shapes of plasma engine structure

图2 等离子发动机结构模态振型
Fig.2 Modal shapes of plasma engine structure

表3 模态分析结果(前6阶)<br/>Tab.3 Modal calculation results of pipeline(the 1st to 6th modal)

表3 模态分析结果(前6阶)
Tab.3 Modal calculation results of pipeline(the 1st to 6th modal)

图3 安装结构设计域<br/>Fig.3 Design domain of mounting structure

图3 安装结构设计域
Fig.3 Design domain of mounting structure

图4 有限元计算模型<br/>Fig.4 Finite element calculation model

图4 有限元计算模型
Fig.4 Finite element calculation model

图5 拓扑优化计算结果<br/>Fig.5 Calculation results of topology optimization

图5 拓扑优化计算结果
Fig.5 Calculation results of topology optimization

图6 结构优化计算模型<br/>Fig.6 Calculation model of structural optimization

图6 结构优化计算模型
Fig.6 Calculation model of structural optimization

图7 支撑结构参数化建模<br/>Fig.7 Parametric modeling of supporting structure

图7 支撑结构参数化建模
Fig.7 Parametric modeling of supporting structure

表4 设计方案1计算结果<br/>Tab.4 Calculation results of design schemeⅠ

表4 设计方案1计算结果
Tab.4 Calculation results of design schemeⅠ

表5 设计方案2计算结果<br/>Tab.5 Calculation results of design schemeⅡ

表5 设计方案2计算结果
Tab.5 Calculation results of design schemeⅡ

图8 拓扑优化计算结果<br/>Fig.8 Calculation results of topology optimization

图8 拓扑优化计算结果
Fig.8 Calculation results of topology optimization

图9 优化结构模型重构<br/>Fig.9 Model reconstruction of optimized structure

图9 优化结构模型重构
Fig.9 Model reconstruction of optimized structure

图10 优化结构模态振型<br/>Fig.10 Modal shapes of optimized structure

图10 优化结构模态振型
Fig.10 Modal shapes of optimized structure

表6 方案性能对比<br/>Tab.6 Performance comparison of different scheme

表6 方案性能对比
Tab.6 Performance comparison of different scheme

图11 位移和应力云图<br/>Fig.11 Nephogram of displacement and stress distribution

图11 位移和应力云图
Fig.11 Nephogram of displacement and stress distribution

图12 随机振动疲劳寿命和应力RMS值计算云图<br/>Fig.12 Distribution nephogram of random vibration fatigue life and RMS stress

图12 随机振动疲劳寿命和应力RMS值计算云图
Fig.12 Distribution nephogram of random vibration fatigue life and RMS stress

[1] 毛根旺,唐金兰.航天器推进系统及其应用[M].西安:西北工业大学出版社,2009.
[2] SACKHEIM R.Overview of United States space propulsion technology and associated space transportation systems[J].Journal of Propulsion and Power,2006,22:1310-1332.
[3] 杜镇志,陈雄,李映坤,等.超音速电弧加热等离子发动机的数值研究[J].真空科学与技术学报,2016,36(2):186-192.
[4] 朱继宏,高欢欢,张卫红,等.航天器整体式多组件结构拓扑优化设计与应用[J].航空制造技术,2014,57(14):26-29.
[5] 高文俊,吕西林.拓扑优化在结构工程中的应用[J].结构工程师,2020,36(6):232-241.
[6] 朱黎明.基于拓扑优化的钢桥结构合理构型研究[J].河南大学学报(自然科学版),2019,49(5):612-617.
[7] 耿志卿,陈昌亚,陆希,等.直接转移方式的木星探测器构型设计及轻量化[J].机械制造与自动化,2020,49(1):150-153.
[8] MLEJNEK H P,SCHIRRMACHER R.An engineer's approach to optimal material distribution and shape finding[J].Computer Methods in Applied Mechanics and Engineering,1993,106(1/2):1-26.
[9] SETHIAN J A,WIEGMANN A.Structural boundary design via level set and immersed interface methods[J].Journal of Computational Physics,2000,163(2):489-528.
[10] BENDSØE M P,KIKUCHI N.Generating optimal topologies in structural design using a homogenization method[J].Computer Methods in Applied Mechanics and Engineering,1988,71(2):197-224.
[11] XIE Y M,STEVEN G P.Evolutionary structural optimization for dynamic problems[J].Computers & Structures,1996,58(6):1067-1073.
[12] 朱继宏,张卫红,邱克鹏.结构动力学拓扑优化局部模态现象分析[J].航空学报,2006,27(4):619-623.
[13] 何芝,雷阳,封硕,等.基于SIMP法的变刚度结构拓扑优化研究[J].装备制造技术,2020(1):8-14.
[14] 滕晓艳,毛炳坤,江旭东.光滑双向渐进结构优化法拓扑优化连续体结构频率和动刚度[J].农业工程学报,2019,35(7):55-61.
[15] 谢浩然,贺媛媛,陶志坚.扑旋翼飞行器气动特性分析及机翼拓扑优化设计[J].南京航空航天大学学报,2020,52(2):280-287.
[16] 王端义,徐文涛.航天结构带频率禁区的动力学拓扑优化设计[J].应用力学学报,2020,37(6):2574-2581.
[17] 张允涛,薛杰,宋少伟,等.轨姿控发动机振动试验夹具结构拓扑优化[J].火箭推进,2023,49(1):93-102.
[18] 袁家军,于登云,陈烈民,等.卫星结构设计与分析[M].北京:中国宇航出版社,2004.
[19] 石波,盛刚,黄雪刚,等.吸气式发动机可调喷管调节片结构优化设计[J].火箭推进,2021,47(3):52-59.
[20] 孟凡涛,胡愉愉.基于频域法的随机振动载荷下飞机结构疲劳分析[J].南京航空航天大学学报,2012,44(1):32-36.
[21] 薛杰,王伟,杜大华,等.姿控动力系统连接螺钉振动疲劳仿真分析研究[J].火箭推进,2019,45(4):38-44.

备注

引言

1 等离子体发动机原安装结构分析

2 等离子体发动机安装结构拓扑优化

3 结论

期刊信息