摘要
针对航天器随机振动设计载荷全频段法往往过于保守的问题,根据随机振动理论,分析了航天器随机振动设计载荷有限频段法的原理;在白噪声基础激励下,比较了有限频段法与位移等效法的设计载荷。结果显示:在单自由度弹簧质量模型下,有限频段法与位移等效法结果基本相同;在二自由度弹簧质量模型及整星模型下,有限频段法要大于位移等效法的设计载荷。以某卫星为例,分析了结构随机振动响应。分析结果表明:航天器不同结构的收敛频率不同,不同方向的位移收敛频率也不同,因此,应根据结构响应收敛频率来确定有限频段法截取频率。
To solve the problem that design load of spacecraft based on full frequency bandwidth is often on the high side, a basic theory of limited frequency bandwidth is analyzed by random vibra- tion theory. Under white noise, the limited frequency bandwidth method is compared with equiv- alent displacement method. With single-degree-of-freedom, the result of the former method is close to the latter method＇ s, and with two-degree-of-freedom mass-spring model and satellite model, the design load is higher than the latter method＇s. With the example of a satellite, ran dom vibration response is analyzed. The results show that convergence frequencies of different structures and directions are different, so the upper limited frequency is decided by the conver- gence frequency of structure response.
出处
《航天器工程》
2013年第1期49-53,共5页
Spacecraft Engineering
基金
国家重大科技专项工程
关键词
航天器
随机振动
设计载荷
有限频段法
加速度等效
位移等效
spacecraft； random vibration； design loadl limited frequency bandwidth methodequivalent acceleration； equivalent displacement
