مجال التميز | تميز دراسي وبحثي |
البحوث المنشورة |
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البحث (1): | |
عنوان البحث: |
Antiplane shear of an asymmetric sandwich plate |
رابط إلى البحث: |
https://link.springer.com/article/10.1007/s00161-021-00969-6 |
تاريخ النشر: |
26/01/2021 |
موجز عن البحث: |
An asymmetric three-layered laminate with prescribed stresses along the faces is considered. The outer layers are assumed to be much stiffer than the inner one. The focus is on long-wave low-frequency anti-plane shear. Asymptotic analysis of the original dispersion relation reveals a low-frequency harmonic supporting a slow quasi-static (or static at the limit) decay along with near cut-off wave propagation. In spite of asymmetry of the problem, the leading order shortened polynomial dispersion relation factorises into two simpler ones corresponding to the fundamental mode and the aforementioned harmonic. The associated 1D equations of motion derived in the paper are also split into two second-order operators in line with the factorisation of the shortened dispersion relation. Asymptotically justified boundary conditions are established using the Saint-Venant’s principle modified by taking into account the high-contrast properties of the laminate. |
المؤتمرات العلمية |
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المؤتمر (1): | |
عنوان المؤتمر: |
BAMC2018, British Applied Mathematics Colloquium |
تاريخ الإنعقاد: |
26/03/2018 |
مكان الإنعقاد: |
St Andrews, Scotland, UK |
طبيعة المشاركة: |
Poster presentation |
عنوان المشاركة: |
Anti-plane dynamic shear of strongly inhomogeneous laminates |
ملخص المشاركة: |
Anti-plane dynamic shear of two-layered and three layered laminates is analysed. Two types of high contrast are considered, including composite structure with at least one stiff (thick or thin) layer. It is shown that for both contrast setups the value of the cut-off frequency, corresponding to the lowest vibration mode for a two layer laminate with one free and one fixed faces, as well as for the lowest antisymmetric mode for a three-layered laminate with traction free faces tends to zero. For these modes shortened equations of motion are derived. Some of them appear to be valid over the whole low-frequency range, while the range of validity of others is restricted to narrow vicinities of the cut-off frequencies. Numerical data illustrating comparisons of exact and asymptotic results are presented. |
الرابط: |
http://www.mcs.st-and.ac.uk/~bamc2018/BAMC2018_timetable.pdf |
المؤتمر (2): | |
عنوان المؤتمر: |
Dynamical Systems – Theory and Applications (DSTA 2019) |
تاريخ الإنعقاد: |
02/12/2019 |
مكان الإنعقاد: |
Lodz. Poland |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Two-mode long-wave low-frequency approximations for anti-plane shear deformation of a high-contrast asymmetric laminate |
ملخص المشاركة: |
The anti-plane shear of a three-layered laminate of an asymmetric structure is considered. The chosen geometry of the laminate couples its symmetric and anti-symmetric motions. A high contrast in mechanical properties of the inner and outer layers is assumed. The types of contrast for which the lowest cut-off frequency of the first harmonic is close to zero are revealed. In case of a laminate with traction-free faces two-mode approximations of the exact dispersion relations incorporating both the fundamental mode and the first harmonic are derived. The accuracy of the asymptotic approximations is tested versus the solutions of the original dispersion relation. The associated 2D differential equations of motion are developed. In addition, the boundary conditions based on the Saint-Venant principle are proposed. |
المؤتمر (3): | |
عنوان المؤتمر: |
9th computing and mathematics postgraduate research day |
تاريخ الإنعقاد: |
10/04/2019 |
مكان الإنعقاد: |
Keele University |
طبيعة المشاركة: |
Poster presentation |
عنوان المشاركة: |
Anti-plane dynamic shear of three-layered asymmetric high-contrast plate |
ملخص المشاركة: |
Anti-plane dynamic shear of asymmetric three-layered laminates is analysed.One type of high contrast is considered, including composite structure with at least one stiff (thick or thin) layer. It is shown the value of the cut-off frequency, corresponding to the lowest vibration mode for three-layered asymmetric plate with traction free faces tends to zero. Numerical data illustrating comparisons of exact and asymptotic results are presented. |
المؤتمر (4): | |
عنوان المؤتمر: |
EURODYN 2020 |
تاريخ الإنعقاد: |
23–26 /11/2020 |
مكان الإنعقاد: |
Athens, Greece |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
A TWO MODE NON-UNIFORM APPROXIMATION FOR AN ELASTIC ASYMMETRIC SANDWICH |
ملخص المشاركة: |
An elastic asymmetric sandwich is considered under the assumption that the stiffness and density of thin skin layers are much greater than those of a core layer. It is shown that for typical values of problem parameters the lowest shear resonance frequency appears to be asymptotically small, while the rest of thickness resonances do not belong to a low-frequency range. As an example, a scalar antiplane problem in linear elasticity is studied. A polynomial long-wave low-frequency approximation of the full dispersion relation is derived. It governs two vibration modes including the fundamental one and the lowest harmonic. Without asymmetry the dispersion relation splits into two parts corresponding to symmetric and antisymmetric modes [1], simplifying analysis drastically. It is remarkable that for the chosen set of problem parameters the derived approximation is not asymptotically uniform and is only valid over narrow non-overlapping vicinities of zero and the lowest shear thickness resonance frequencies. This is in contrast to the earlier considered setup of a similar laminate with the thick skin layers, for which the associated asymptotic behaviour is uniform [2]. The same observation is also true for in-plane motion of a symmetric laminate, see [3] for further detail. |
الرابط: |
المرفقات
- https://uksacb.org/wp-content/uploads/keele_Cert.jpg
- https://uksacb.org/wp-content/uploads/Poland1.jpg
- https://uksacb.org/wp-content/uploads/Poland1paper.jpg
- https://uksacb.org/wp-content/uploads/Alkinidri2021_Article_AntiplaneShearOfAnAsymmetric.pdf
- https://uksacb.org/wp-content/uploads/AlkinidripaperPeerreviewUORODAYN.pdf
- https://uksacb.org/wp-content/uploads/AlkinidriparticipationletterUORODAYN.pdf
- https://uksacb.org/wp-content/uploads/Kaplunov2021_Article_AntiplaneShearOfAnAsymmetricSa.pdf
- https://uksacb.org/wp-content/uploads/KeelePGRdayposter5.pdf