火箭推进

针对液体火箭发动机承力机架，开展复合材料机架的初步设计及探索应用研究。通过对原金属机架结构设计特点分析，提出了一种碳纤维增强复合材料机架的设计方案，并对其进行了力学性能预测及设计参数影响分析等方面研究工作；最后，采用有限元软件ANSYS的APDL语言开发了复合材料机架的计算程序，该程序基于损伤累积理论，包含结构应力分析、材料的失效判断及材料的性能退化3个主要循环过程，通过仿真手段模拟了在载荷增加过程中结构内部产生损伤，并逐渐累积直至破坏的整个过程。仿真分析结果表明：复合材料的应用可在满足原机架强度、刚度和稳定性等设计要求基础上，相对于原结构实现了50%的减重。

Preliminary design and applied exploration of the composite thrust frame of a liquid-propellant rocket engine are performed in this paper. Based on the design features for original thrust frame metal structure, a design scheme of the carbon fiber reinforced composite thrust frame is proposed, its mechanics performance is predicted, and the effect factors on its design parameters are analyzed. APDL (ANSYS Parametric Design Language) of the finite element software ANSYS is used to develop the computing procedure of the composite thrust frame, which is based on damage accumulation theory, including stress analysis, failure evaluation and material property degradation. The internal structure injure in the loading process and the whole process of the injury accumulation until damage was simulated. The simulation analysis result shows that the composite can meet the design requirement of thrust frame strength, stiffness and stability, and the weight is decrease by 50%, compared with the original structure.

引言
1 机架原结构设计特点
2 复合材料机架基本设计原则
3 复合材料强度分析方法
4 复合材料机架设计
5 结论

图1 助推机架原设计示意图<br/>Fig.1 Schematic diagram of original thrust frame

图1 助推机架原设计示意图
Fig.1 Schematic diagram of original thrust frame

图2 复合材料机架静强度分析流程<br/>Fig.2 Flow chart of static strength analysis for composite thrust frame

图2 复合材料机架静强度分析流程
Fig.2 Flow chart of static strength analysis for composite thrust frame

图3 复合材料机架三维模型<br/>Fig.3 3D model of composite thrust frame

图3 复合材料机架三维模型
Fig.3 3D model of composite thrust frame

表1 复合材料机架铺层设计方案<br/>Tab.1 Stacking sequence design scheme of composite thrust frame

表1 复合材料机架铺层设计方案
Tab.1 Stacking sequence design scheme of composite thrust frame

图4 复合材料机架在飞行工况载荷下变形图<br/>Fig.4 Deformed shape of composite thrust frame under flight conditions

图4 复合材料机架在飞行工况载荷下变形图
Fig.4 Deformed shape of composite thrust frame under flight conditions

图5 复合材料机架破坏位置<br/>Fig.5 Failure position of composite thrust frame

图5 复合材料机架破坏位置
Fig.5 Failure position of composite thrust frame

图6 复合材料机架的一阶失稳模态<br/>Fig.6 The first-order buckling mode of composite thrust frame

图6 复合材料机架的一阶失稳模态
Fig.6 The first-order buckling mode of composite thrust frame

图7 加注状态载荷作用下复合材料机架的变形情况<br/>Fig.7 Deformation of composite thrust frame under filling state loading

图7 加注状态载荷作用下复合材料机架的变形情况
Fig.7 Deformation of composite thrust frame under filling state loading

图8 半梁端部高度对机架变形量、破坏载荷的影响<br/>Fig.8 Influence of half-beam end height on thrust frame deformation and failure load

图8 半梁端部高度对机架变形量、破坏载荷的影响
Fig.8 Influence of half-beam end height on thrust frame deformation and failure load

图9 机架半梁端部约束形式<br/>Fig.9 Restraint conditions of half-beam end of thrust frame

图9 机架半梁端部约束形式
Fig.9 Restraint conditions of half-beam end of thrust frame

图10 半梁端部约束形式改变对结构变形量和破坏载荷的影响<br/>Fig.10 Influence of half-beam end restraint conditions on structure deformation and failure load

图10 半梁端部约束形式改变对结构变形量和破坏载荷的影响
Fig.10 Influence of half-beam end restraint conditions on structure deformation and failure load

图11 半梁端部进行“切角”处理 <br/>Fig.11 Cutout processing at half-beam end

图11 半梁端部进行“切角”处理
Fig.11 Cutout processing at half-beam end

表2 半梁端部“切角”前后机架不同铺层应力分布<br/>Tab.2 Stress distribution of different layers of cutout at half-beam end

表2 半梁端部“切角”前后机架不同铺层应力分布
Tab.2 Stress distribution of different layers of cutout at half-beam end

[1]EHRLICH CarlF, Jr. Why the X-33 venture star gave SSTO a bad name[C]// Proceedings of AIAA SPACE Conference and Exposition. Pasadena, CA: AIAA, 2009: 111-118.
[2]LETCHWORTH Gary. X-33 reusable launch vehicle de- monstrator, spaceport and range[C]//Proceedings of AIAA SPACE Conference and Exposition. Long Beach, CA: AIAA, 2011: 11-19.
[3]SMITH John J. Evolved composite structures for Atlas V [C]//Proceedings of The 38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit. Indianapolis, IN: AIAA, 2002: 23-28.
[4]朱宁昌. 液体火箭发动机设计（上）[M]. 北京: 宇航出版社, 1994.
[5]陈朝辉, 肖加余, 曾竟成. 复合材料在航天主承力结构及热结构上的应用[C]//. 全国首届青年复合材料学术交流会论文集, 北京: 中国复合材料学会, 2006.
[6]彭超义. 空间运载器推力支架用复合材料管件轴压性能研究[D]. 长沙: 国防科技大学, 2006.
[7]何昆, 耿东兵, 赵伟栋, 等. 树脂基复合材料发动机机架结构研究[J]. 试验技术与试验机, 2008 (2): 10-12.
[8]马海全, 李竞蔚. 复合材料桁架式发动机支架改型设计分析[J]. 强度与环境, 2006, 33(4): 39-43.
[9]蔡国飙, 李家文, 田爱梅, 等. 液体火箭发动机设计[M]. 北京: 北京航空航天出版社, 2011.
[10]中国航空研究院编. 复合材料结构设计手册[M]. 北京: 航空工业出版社, 2001.
[11]TESERPES K I, LABEAS G, PAPANIKOS P, et al. Strength prediction of bolted joints in graphite/epoxy composite laminates[J]. Composites: Part B, 2000 (33): 521-529.
[12]CAMANHO P P, DAVILA C G, AMBUR D R. Numerical simulation of delamination growth in composite materials: NASA/TP-2001-211041[R]. USA：NASA, 2001.
[13]CAMANHO P　P, MATTHEWS F　L. A progressive damage model for mechanically fastened joints in composites[J]. Journal of composite materials, 1999 (33): 2248-2280.
[14]杨博, 陈永清, 曹正华. 大厚度碳纤维复合材料层压板的试制[J]. 航空制造技术, 2009(增刊), 73-74, 78.

备注

引言

1 机架原结构设计特点

2 复合材料机架基本设计原则

3 复合材料强度分析方法

4 复合材料机架设计

5 结论

期刊信息