Effect of actuation method on hydrodynamics of elastic plates oscillating at resonance

AbstractThe Kirchhoff-Love hypothesis expresses a kinematic constraint that is assumed to be valid for the deformations of a three-dimensional body when one of its dimensions is much smaller than the other two, as is the case for plates. This hypothesis has a long history checkered with the vicissitudes of life: even its paternity has been questioned, and recent rigorous dimension-reduction tools (based on standard $\varGamma $ Γ -convergence) have proven to be incompatible with it. We find that an appropriately revised version of the Kirchhoff-Love hypothesis is a valuable means to derive a two-dimensional variational model for elastic plates from a three-dimensional nonlinear free-energy functional. The bending energies thus obtained for a number of materials also show to contain measures of stretching of the plate’s mid surface (alongside the expected measures of bending). The incompatibility with standard $\varGamma $ Γ -convergence also appears to be removed in the cases where contact with that method and ours can be made.

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Simulation of 2-Coil and 4-Coil Magnetic Resonance Wearable WPT Systems

Proceedings ◽

10.3390/proceedings2021068013 ◽

2021 ◽

Vol 68 (1) ◽

pp. 13

Author(s):

Yixuan Sun ◽

Stephen Beeby

Keyword(s):

Power Efficiency ◽

Power Transmission ◽

Rotation Angle ◽

Wireless Power ◽

Peak Efficiency ◽

Frequency Splitting ◽

At Resonance ◽

Higher Power ◽

The Impact ◽

Proper Frequency

This paper presents the COMSOL simulations of magnetically coupled resonant wireless power transfer (WPT), using simplified coil models for embroidered planar two-coil and four-coil systems. The power transmission of both systems is studied and compared by varying the separation, rotation angle and misalignment distance at resonance (5 MHz). The frequency splitting occurs at short separations from both the two-coil and four-coil systems, resulting in lower power transmission. Therefore, the systems are driven from 4 MHz to 6 MHz to analyze the impact of frequency splitting at close separations. The results show that both systems had a peak efficiency over 90% after tuning to the proper frequency to overcome the frequency splitting phenomenon at close separations below 10 cm. The four-coil design achieved higher power efficiency at separations over 10 cm. The power efficiency of both systems decreased linearly when the axial misalignment was over 4 cm or the misalignment angle between receiver and transmitter was over 45 degrees.

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Self-dual singularity through lasing and antilasing in thin elastic plates

Physical Review B ◽

10.1103/physrevb.103.134101 ◽

2021 ◽

Vol 103 (13) ◽

Author(s):

M. Farhat ◽

P.-Y. Chen ◽

S. Guenneau ◽

Y. Wu

Keyword(s):

Elastic Plates ◽

Thin Elastic Plates

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Vibration Amplitude Suppression Control of Industrial Machine Driven at Resonance Frequency

2020 IEEE 16th International Workshop on Advanced Motion Control (AMC) ◽

10.1109/amc44022.2020.9244358 ◽

2020 ◽

Author(s):

Hikaru Sato ◽

Toshimasa Miyazaki ◽

Yoshihisa Hojo

Keyword(s):

Resonance Frequency ◽

Vibration Amplitude ◽

At Resonance ◽

Industrial Machine

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Existence of solutions for functional boundary value problems at resonance on the half-line

Boundary Value Problems ◽

10.1186/s13661-020-01459-5 ◽

2020 ◽

Vol 2020 (1) ◽

Author(s):

Bingzhi Sun ◽

Weihua Jiang

Keyword(s):

Boundary Value Problems ◽

Banach Spaces ◽

Existence Of Solutions ◽

Boundary Value ◽

Coincidence Degree ◽

Degree Theory ◽

Half Line ◽

Projection Scheme ◽

At Resonance ◽

Functional Boundary

Abstract By defining the Banach spaces endowed with the appropriate norm, constructing a suitable projection scheme, and using the coincidence degree theory due to Mawhin, we study the existence of solutions for functional boundary value problems at resonance on the half-line with $\operatorname{dim}\operatorname{Ker}L = 1$ dim Ker L = 1 . And an example is given to show that our result here is valid.

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Spacetime modulation in floating thin elastic plates

Physical Review B ◽

10.1103/physrevb.104.014308 ◽

2021 ◽

Vol 104 (1) ◽

Author(s):

Mohamed Farhat ◽

Sebastien Guenneau ◽

Pai-Yen Chen ◽

Ying Wu

Keyword(s):

Elastic Plates ◽

Thin Elastic Plates

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Critical Temperatures for Vibrations and Buckling of Magneto-Electro-Elastic Nonlocal Strain Gradient Plates

Nanomaterials ◽

10.3390/nano11010087 ◽

2021 ◽

Vol 11 (1) ◽

pp. 87

Author(s):

Giovanni Tocci Monaco ◽

Nicholas Fantuzzi ◽

Francesco Fabbrocino ◽

Raimondo Luciano

Keyword(s):

Strain Gradient ◽

Thermal Environment ◽

Scale Effects ◽

Nonlocal Theory ◽

Elastic Plates ◽

Critical Temperatures ◽

Buckling Behavior ◽

Linear Vibrations ◽

Nonlocal Strain Gradient ◽

Plate Kinematics

An analytical method is presented in this work for the linear vibrations and buckling of nano-plates in a hygro-thermal environment. Nonlinear von Kármán terms are included in the plate kinematics in order to consider the instability phenomena. Strain gradient nonlocal theory is considered for its simplicity and applicability with respect to other nonlocal formulations which require more parameters in their analysis. Present nano-plates have a coupled magneto-electro-elastic constitutive equation in a hygro-thermal environment. Nano-scale effects on the vibrations and buckling behavior of magneto-electro-elastic plates is presented and hygro-thermal load outcomes are considered as well. In addition, critical temperatures for vibrations and buckling problems are analyzed and given for several nano-plate configurations.

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