Advances in damping analysis and design of fiber reinforced composite material structures 纖維增強復合材料結(jié)構(gòu)阻尼研究進展
( 3 ) . linear quadratic regulation method is used to design the optimal feed back controller for the composite material structures with the piezoceramics embedded ( 3 ) .對壓電復合智能材料結(jié)構(gòu)設計了線性二次型最優(yōu)控制器。
Analysis and compution proves that those dsps are precise to identify the damage of structures . so these dsps could be applied in shm for composite materials structures 分析計算的結(jié)果表明,幾種標識量都有較好的識別精度,能較可靠地應用用于復合材料結(jié)構(gòu)的損傷識別和健康監(jiān)控。
This paper starts with the dynamic characteristics of structures , seeks the damage sign parameters ( dsp ) of composite materials structures , which have essential relations with the damage / healthy status 本文從復合材料結(jié)構(gòu)的動力學特性入手,找出能較方便地反映結(jié)構(gòu)損傷失效的特征標識量。
The main research works done and conclusions extracted are listed as follows . ( 1 ) . based on the piezoelectric equation , the strain and stress distribution are analyzed for the composite material structures with piezoelectric materials embedded inside 從壓電材料的壓電方程出發(fā),針對埋入式壓電片,分析埋入式壓電片在和結(jié)構(gòu)一起發(fā)生變形時基體結(jié)構(gòu)材料和壓電材料的應力應變的分布規(guī)律和關系。
The conclusions obtained as follows : firstly , the structure ' s free frequency is decreased by the reduction of the mechanical property of the material with the increasing temperature ; secondly the thermal stress produced by the temperature gradient may decrease or enlarge the structures natural frequency ; thirdly , the variety of natural frequency of the alloy structures effected by the heat effect apparently higher than that of the composite material structures 最后,采用ansys程序分析了合金材料、復合材料的板、彈體結(jié)構(gòu)的熱振動特性。在不同的熱載條件下,取得以下結(jié)論:升溫導致的材料機械性能下降都會降低結(jié)構(gòu)固有頻率,而溫度梯度產(chǎn)生的熱應力可能降低也可能提高結(jié)構(gòu)的固有頻率;金屬材料結(jié)構(gòu)的固有頻率受溫度的影響要比復合材料結(jié)構(gòu)的固有頻率受溫度的影響要明顯。
This article gives the subsistent ability and the analysis result of intensity after repair in the open field airplane composite material structure by research the intensity , rigid and repair problem under a axis compress loads on a typical three stiffened composite laminate which has a penetrability crack ( a scatter damage ) by a shrapnel 本文通過飛機典型復合材料三加筋層壓板結(jié)構(gòu)在被彈片劃開一穿透性切口(離散源損傷)后,在軸向壓縮載荷作用下所產(chǎn)生的強度、剛度以及修理問題展開了技術研究及探討,給出軍機復合材料加筋板在彈擊后生存力以及外場修理后強度恢復分析結(jié)果。
This dissertation deals with the active vibration control strategy using the embedded piezoceramics as both actuators and sensors . with several ceramics embedded into the composite material structures during the manufacturing process without knowing the structural behavior in advance , this dissertation makes use of a self identification procedure to get the models of the system . apparently , the on - line self identification method enable people to update the models of system 另外本文利用埋入復合材料結(jié)構(gòu)中的壓電傳感器和驅(qū)動器對其進行模型識別而得出結(jié)構(gòu)的動力學模型,再將該模型用于控制器的設計,這樣做的好處是如果結(jié)構(gòu)本身或者約束、環(huán)境等發(fā)生變化后,可以很方便地對結(jié)構(gòu)的模型重新進行在線識別,及時更新控制參數(shù),避免控制失效,而且不需要事先知道結(jié)構(gòu)的其它屬性。