摘要
对高精度、大面积不可展双曲反射面的制造问题 ,提出了基于“离散钉模、真空负压、蜂窝夹层、应力释放、回弹补偿”的高精度反射面板成形原理 ;建立了四边自由面内多点约束的薄板大挠度弯曲解法及夹层板成形过程仿真模型 ,用于确定成形工艺参数 ;利用动力显式和静力隐式算法相结合的方法实现成形过程仿真 ;通过开缝和开槽方法释放面内压应力 ,确定了面板开缝和开槽方案 ;通过逆向修正离散模包络面 ,使其与成形模拟得到的夹层板型面误差最小 ,得到模具修正因子 ,补偿回弹误差 .在此基础上开发了夹层板精密成形CAE系统 .该方法制造的面板型面精度RMS达到 2 5 μm以下 。
To solve the precision forming problem of the antenna panels with large non-developable double-curvature surface, the precision forming principle was proposed, based on discrete nails die, vacuum negative pressure, honeycomb sandwich, stress release in-plane, and resilience compensation. The problem of rectangle thin plate with free edges and constrained at arbitrary inner points with large deflection was discussed. An explicit/implicit hybrid finite element method was used to simulate the forming process and resilience to determine the processing parameters. The slotting and notching techniques were used for releasing the compression stresses of panel in order to ensure good fitness of panel on nails die. The resilience compensation was carried out by modifying discrete nails die, and the adjusting coefficient of nail-head height was obtained by minimizing the shape error between the modified surface and simulation shape. The CAE system for precision forming of antenna panels has been used for several actual projects of compact antenna test range and millimeter wave antenna. The root mean square (RMS) of reflector panel can reach below 25 μm.
出处
《北京航空航天大学学报》
EI
CAS
CSCD
北大核心
2004年第4期296-300,共5页
Journal of Beijing University of Aeronautics and Astronautics
基金
国家自然科学基金 ( 5 9975 0 0 5 )
国防预研基金资助项目 ( 99J18 4 7HK0 13 8)
关键词
天线反射器
精密成形
紧缩场
离散钉模
蜂窝夹层板
Computer aided manufacturing
Deflection (structures)
Dies
Forming
Plates (structural components)
Sandwich structures
