Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory
This paper is devoted to examining the nonlinear vibrational behaviors of functionally graded (FG) sandwich nanobeams in the presence of initial geometric imperfection. Based on the nonlocal strain gradient theory, the governing equation of the FG sandwich nanobeam with consideration of the Von-Karm...
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Format: | Journal Article |
Language: | English |
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2021
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Online Access: | https://hdl.handle.net/10356/151554 |
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author | Liu, Hu Lv, Zheng Wu, Han |
author2 | School of Mechanical and Aerospace Engineering |
author_facet | School of Mechanical and Aerospace Engineering Liu, Hu Lv, Zheng Wu, Han |
author_sort | Liu, Hu |
collection | NTU |
description | This paper is devoted to examining the nonlinear vibrational behaviors of functionally graded (FG) sandwich nanobeams in the presence of initial geometric imperfection. Based on the nonlocal strain gradient theory, the governing equation of the FG sandwich nanobeam with consideration of the Von-Karman nonlinearity and initial geometric imperfection is derived. The nonlinear oscillator frequency is obtained with the aid of He's variational principle. Three types of nanobeams, i.e., FG nanobeam (Type A), sandwich nanobeam with homogeneous core and FG skins (Type B), and sandwich nanobeam with FG core and homogeneous skins (Type C) are taken into account. A cosine function similar to the mode shape form is employed to describe the geometric imperfection mode. Firstly, the present theoretical model is verified by comparing with previous perfect FG sandwich beams. Then, several key parameters such as the power-law exponent, the amplitudes of the nonlinear oscillator and the geometric imperfection, as well as the nonlocal and material characteristic parameters are investigated in detail. Finally, apart from the structural types, the influence of thickness distribution scheme is also thoroughly elucidated. The results obtained in this paper are helpful for exploring the FG sandwich design to enhance the mechanical performance of nano-devices. |
first_indexed | 2024-10-01T06:34:04Z |
format | Journal Article |
id | ntu-10356/151554 |
institution | Nanyang Technological University |
language | English |
last_indexed | 2024-10-01T06:34:04Z |
publishDate | 2021 |
record_format | dspace |
spelling | ntu-10356/1515542021-06-30T02:27:00Z Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory Liu, Hu Lv, Zheng Wu, Han School of Mechanical and Aerospace Engineering School of Civil and Environmental Engineering Engineering::Mechanical engineering Engineering::Civil engineering Nonlinear Vibration Functionally Graded This paper is devoted to examining the nonlinear vibrational behaviors of functionally graded (FG) sandwich nanobeams in the presence of initial geometric imperfection. Based on the nonlocal strain gradient theory, the governing equation of the FG sandwich nanobeam with consideration of the Von-Karman nonlinearity and initial geometric imperfection is derived. The nonlinear oscillator frequency is obtained with the aid of He's variational principle. Three types of nanobeams, i.e., FG nanobeam (Type A), sandwich nanobeam with homogeneous core and FG skins (Type B), and sandwich nanobeam with FG core and homogeneous skins (Type C) are taken into account. A cosine function similar to the mode shape form is employed to describe the geometric imperfection mode. Firstly, the present theoretical model is verified by comparing with previous perfect FG sandwich beams. Then, several key parameters such as the power-law exponent, the amplitudes of the nonlinear oscillator and the geometric imperfection, as well as the nonlocal and material characteristic parameters are investigated in detail. Finally, apart from the structural types, the influence of thickness distribution scheme is also thoroughly elucidated. The results obtained in this paper are helpful for exploring the FG sandwich design to enhance the mechanical performance of nano-devices. 2021-06-30T02:27:00Z 2021-06-30T02:27:00Z 2019 Journal Article Liu, H., Lv, Z. & Wu, H. (2019). Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory. Composite Structures, 214, 47-61. https://dx.doi.org/10.1016/j.compstruct.2019.01.090 0263-8223 https://hdl.handle.net/10356/151554 10.1016/j.compstruct.2019.01.090 2-s2.0-85061060738 214 47 61 en Composite Structures © 2019 Elsevier Ltd. All rights reserved. |
spellingShingle | Engineering::Mechanical engineering Engineering::Civil engineering Nonlinear Vibration Functionally Graded Liu, Hu Lv, Zheng Wu, Han Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory |
title | Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory |
title_full | Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory |
title_fullStr | Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory |
title_full_unstemmed | Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory |
title_short | Nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory |
title_sort | nonlinear free vibration of geometrically imperfect functionally graded sandwich nanobeams based on nonlocal strain gradient theory |
topic | Engineering::Mechanical engineering Engineering::Civil engineering Nonlinear Vibration Functionally Graded |
url | https://hdl.handle.net/10356/151554 |
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