Ultraviolet-activated frequency control of beams and plates based on isogeometric analysis
Ultraviolet-activated frequency control of beams and plates based on isogeometric analysis
复制标题
基于等几何分析的梁和板的紫外激活频率控制
DOI：
10.1115/1.4038948
复制
发表时间：
2018
影响因子：
1.7
通讯作者：
Hornsen Tzou
中科院分区：
文献类型：
--
作者：
Yujie Guo;Hornsen Tzou
一种新型的光激活形状记忆聚合物（LaSMP）智能材料具有形状记忆行为和刚度变化，通过紫外光（UV）曝光。这种动刚度为工程结构提供了一种新的非接触驱动机构。等几何分析（伊加）采用高阶、高连续的非均匀有理B样条（NURBS）作为基函数，自然满足Euler-Bernoulli梁和Kirchhoff板理论的C1连续性要求。与传统的梁、板单元相比，伊加不需要额外的转动自由度，同时能提供精确的计算结果。本文提出了基于伊加的LaSMP全层和部分层合梁板结构的紫外光激励频率控制方法。对于LaSMP部分层合板的分析，提出了伊加框架下的有限单元法来处理包含修剪特征的NURBS几何。所提出的等几何方法的精度和效率通过几个数值例子在频率控制中证明。结果表明，利用LaSMPs可以实现梁板结构的宽带频率控制。此外，改变梁和板上的LaSMP贴片尺寸进一步拓宽了其频率控制范围。研究表明：（2）梁和板结构的最大频率操纵率分别达到24.30%和16.75%，表明了LaSMPs诱导结构振动控制的可行性。
A new light-activated shape memory polymer (LaSMP) smart material exhibits shape memory behaviors and stiffness variation via ultraviolet (UV) light exposures. This dynamic stiffness provides a new noncontact actuation mechanism for engineering structures. Isogeometric analysis (IGA) utilizes high order and high continuity nonuniform rational B-spline (NURBS) as basis functions which naturally fulfills C1-continuity requirement of Euler–Bernoulli beam and Kirchhoff plate theories. Compared with the traditional finite elements of beams and plates, IGA does not need extra rotational degrees-of-freedom while providing accurate results. The UV light-activated frequency control of LaSMP fully and partially laminated beam and plate structures based on the IGA is presented in this study. For the analysis of LaSMP partially laminated plates, the finite cell approach in the framework of IGA is proposed to handle NURBS geometries containing trimming features. The accuracy and efficiency of the proposed isogeometric approach are demonstrated via several numerical examples in frequency control. The results show that, with LaSMPs, broadband frequency control of beam and plate structures can be realized. Furthermore, changing LaSMP patch sizes on beams and plates further broadens its frequency control ranges. Studies suggest that: (1) the newly developed IGA combining finite cell approach is an effective numerical tool and (2) the maximum frequency manipulation ratios of beam and plate structures, respectively, reach 24.30% and 16.75%, which demonstrates the feasibility of LaSMPs-induced vibration control of structures.