Piezoelectric Shell Research Articles

RFOR-DQHFEM: Hybrid relaxed first-Order reliability and differential quadrature hierarchical finite element method for multi-physics reliability analysis of conical shells

In this current work, a hybrid reliability analysis and theoretical frequency technique are suggested for the reliability response of conical shells. Two levels of analyses are proposed as the main loop of the reliability method for finding the failure probability and the second level applied in the main loop for giving the performance function of frequency applied in conical shell structures with multi-physics vibration analysis. A dynamical adjusting procedure is proposed for computing the relaxed factor using the enough descent condition inside the reliability method. The superior convergence rate is considered for selecting the relaxed factor of the proposed first-order reliability method named RFORM. An elastic-electro-mechanical model based on the Higher-Order Shear Deformation Theory (HSDT) is extended for frequency analysis of conical shells. The innovative numerical procedure named Differential Quadrature Hierarchical Finite Element Method (DQHFEM) as a robust framework for giving the vibration behavior of studied mechanical structures is applied for solving motion equations. The developing DQHFEM and RFORM are applied for the laminated, nanocomposite, and piezoelectric conical shell structures with multi-source uncertainties. Increasing the volume percentage of nanoparticles from 0% to 10% significantly enhances the reliability index, with carbon nanoparticles showing a 132% increase, silica nanoparticles showing a 97% increase, and other nanoparticles showing an approximate 40% increase. Also, as moisture content increases from 0% to 30%, the reliability index for a thickness-to-large-radius ratio of 0.2 drops by about five times. Excessive moisture levels (above 20%) result in a negative reliability index, indicating a hazardous condition.

Multi-field coupling and vibration analysis of a piezoelectric semiconductor cylindrical shell

Multi-field coupling and vibration analysis of a piezoelectric semiconductor cylindrical shell

BBB-penetrating magnetoelectric nanoparticles with sustainable Gel formulation for enhanced chemotherapy and reduced postoperative glioma recurrence

Overcoming blood–brain barrier (BBB), reducing drug resistance and inhibiting postoperative recurrence are the huge challenges of glioma treatment. Herein, a magnetoelectric nanoparticle, applying CoFe2O4 as magnetic core, BaTiO3 as piezoelectric shell and polyethylene glycol-connected I6P8 peptide as surface coating (CBPI), was used for glioma-targeted treatment. This nanoparticle could down-regulate tight junction proteins of BBB via magnetoelectric effect, synergized with I6P8 peptide, to achieve the enhanced BBB permeability and glioma targeting. Under magnetic field activation, this nanoparticle, after doxorubicin loading to formulate CBPID, could accomplish magnetoelectricity and pH-responsive drug release, and generate mild reactive oxygen species to sensitize the chemotherapy through c-Jun N-terminal kinase phosphorylation pathway. Importantly, CBPID facilitated intraoperative cavity administration with magnetic immobilization after easy doping to Surgiflo filler, benefiting the repeated magnetoelectric-activated therapy to inhibit glioma postoperative recurrence. Moreover, CBPID could be mostly excreted through feces after intravenous injection, which did not cause obvious blood and organ abnormalities and even improved the behavioral abnormalities caused by glioma.

Three-dimensional vibration analysis of multilayered composite and functionally graded piezoelectric plates and shells

In the present paper, a coupled 3D exact electro-elastic shell model for Functionally Graded (FG) and composite piezoelectric structures is proposed. Primary variables of the electro-elastic model are the electric potential and the three displacement components. The model allows to evaluate the piezoelectric effect in terms of frequencies and vibration modes. Both closed and open circuit configurations are analyzed and compared. The 3D equilibrium equations and the 3D divergence electric displacement equation for spherical shells give the set of partial differential equations for the electro-elastic problem. The proposed model for spherical shells automatically degenerates into simpler models for plates and cylindrical shells via properly considerations on radii of curvature along in-plane directions. The orthogonal mixed curvilinear coordinates α, β and z are employed. The partial differential governing equations have constant coefficients considering fictitious layers and they are solved using the Navier harmonic form and the exponential matrix method. These features lead to an exact solution for simply-supported boundary conditions. Free vibration analyses are conducted and circular frequencies for the first three thickness vibration modes are computed. After a global assessment phase to verify the correctness of the developed model, new benchmarks are proposed: different thickness ratios and material configurations are investigated. The present work can be intended as a reference general solution for those scientists interested in the study of piezoelectric structures via 2D analytical and numerical formulations.

Nonlinear poro-thermo-forced vibration in curved sandwich magneto-electro-elastic shells under hygrothermal environment

This research employs a multiple scales perturbation approach to evaluate the nonlinear wave propagation behaviors of a doubly curved sandwich composite piezoelectric shell with a flexible core in a hygrothermal environment. Stress and strain calculations for the flexible core and face sheets are carried out using Reddy's third-order shear deformation theory (TSDT) and third-order polynomial theory, respectively. The study explores the synergistic effects of a multilayered shell, flexible core, and magneto-rheological layer (MR) in revealing the nonlinearity of both in-plane and vertical moment within the core. The Halpin–Tsai model is employed to derive the properties of polymer/carbon nanotube/fiber (PCF) and polymer/graphene platelet/fiber (PGF) three-phase composite shells. The governing equations for the multiscale shell are derived using Hamilton's formulation. The research investigates temperature variations, diverse distribution patterns, curvature ratios, and magnetic fields through numerical analysis, presenting the results graphically and prior research has demonstrated the accuracy of these methods. Notably, these factors exert significant influence on the frequency-amplitude curves of the smart structure.

Extracting longitudinal waves by utilizing the symmetry of piezoelectric sphere

Dividing the P- and S- wave components from measured body wave signals is a pivotal yet formidable task for various seismic monitoring devices. In contrast to the commonly employed post processing methods, here, we report a sensor designed to directly extract P-wave signals by filtering out the S-wave component from body waves. The design principle of the sensor capitalizes on the inherent symmetry of a spherical piezoelectric shell and body waves, resulting in the superposition of P-wave excitation charges while concurrently canceling out S-wave excitation charges. The validity of this concept was first confirmed through theoretical analysis and numerical simulations. Laboratory tests further substantiated that the sensor response to P-waves surpasses that to S-waves by two orders of magnitude. The reported sensor sheds sights on the processing of body waves with hardware and validates a new pathway for improving the performance of existing related devices.

Remotely Controlled Surface Charge Modulation of Magnetoelectric Nanogenerators for Swift and Efficient Drug Delivery.

We have developed a highly efficient technique of magnetically controlled swift loading and release of doxorubicin (DOX) drug using a magnetoelectric nanogenerator (MENG). Core-shell nanostructured MENG with a magnetostrictive core and piezoelectric shell act as field-responsive nanocarriers and possess the capability of field-triggered drug release in a cancerous environment. MENGs generate a surface electric dipole when subjected to a magnetic field due to the strain-mediated magnetoelectric effect. The capability of directional magnetic field-assisted modulation of the surface electrical dipole of MENG provides a mechanism to create/break ionic bonds with DOX molecules, which facilitates efficient drug attachment and on-demand swift detachment of the drug at a targeted site. The magnetic field-assisted drug-loading mechanism was minutely analyzed using spectrophotometry and Raman spectroscopy. The detailed time-dependent analysis of controlled drug release by the MENG under unidirectional and rotating magnetic field excitation was conducted using field-emission scanning electron microscopy, energy-dispersive X-ray, and atomic force microscopic measurements. In vitro, experiments validate the cytocompatibility and magnetically assisted on-demand and swift DOX drug delivery by the MENG near MCF-7 breast cancer cells, which results in a significant enhancement of cancer cell killing efficiency. A state-of-the-art experiment was performed to visualize the nanoscale magnetoelectric effect of MENG using off-axis electron holography under Lorentz conditions.

A novel smart hybrid multimorph piezoelectric spherical shell cloak for broadband near-perfect underwater acoustic camouflage applications

Non-visual auditory camouflage plays a major role in the art of underwater deception. In this work, a hybrid active/semi-active omnidirectional cloaking shell structure composed of alternate complementary piezoelectric and smart viscoelastic (PZT/SVE) actuator layers is proposed that can effectively conceal a three dimensional underwater macroscopic object from broadband incident sound waves. The smart hybrid structure incorporates a finite sequence of fully active parallel-connected multimorph PZT constraining layers inter-stacked with semi-active SVE core layers both of which are collaboratively operative in the framework of a Particle Swarm Optimized (PSO) multiple-input multiple-output active damping control (MIMO-ADC) scheme. The elasto-acoustic modeling of the problem is conducted by coupling the spatial state space methodology based on the classical three-dimensional exact piezoelasticity theory with the wave equations for the inner and outer acoustic domains. The acoustic cloaking performance of proposed configuration is evaluated for four distinct classes of highly functional SVE interlayer materials with tunable (field-dependent) rheological properties, namely, magnetorheological elastomer (MRE), shape memory polymer (SMP), electrorheological fluid (ERF), and magnetorheological shear thickening polishing fluid (MRSTPF). Extensive numerical results reveal significant broadband reductions of the far-field backscattering amplitude in the (f∞θ=π,kexRex)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\left|{f}_{\\infty }\\left(\ heta =\\pi ,{k}_{\ ext{ex}}{R}_{\ ext{ex }}\\right)\\right|)$$\\end{document} as well as the percentage error of external cloaked field (%Err)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(\\%\ ext{Err})$$\\end{document} by incorporating a sufficient number of smart multimorph PZT/SVE material layers. Furthermore, it is concluded that comparable low frequency acoustic cloaking effects is possible without expenditure of any external energy just by employing the entirely inactive MRSTPF-based cloak as an alternative to the semiactive or fully active multimorph PZT/SVE cloaks. The outcome of proposed study can advantageously serve as the first step towards practical development and experimental implementation of future high performance smart acoustic cloaking devices with expanded broadband near-perfect omnidirectional invisibility for three dimensional objects of diverse geometries.

Influences of properties of magneto-electro-elastic materials of piezoelectric smart shells

Influences of properties of magneto-electro-elastic materials of piezoelectric smart shells

Electromechanical coupling analysis of geometrically exact functionally graded piezoelectric shells based on weak form quadrature element method

Electromechanical coupling analysis of geometrically exact functionally graded piezoelectric shells based on weak form quadrature element method

Analysis and modeling of two-dimensional piezoelectric semiconductor shell theory

In recent years, there has been a surge in research on piezoelectric semiconductors (PSs). However, studies specifically focused on two-dimensional PS structures remain scarce. In this paper, based on the principle of the virtual work method, the condition of charge continuity and the first-order thickness shear theory, we have established a two-dimensional model to investigate the electromechanical properties of two-dimensional PS shells. The basic field quantities, including the displacement, the electric potential and the carrier concentration perturbations were Fourier expanded along the width direction, and then the governing equations were successfully derived. The differential quadrature method was used to obtain numerical results for the PS shells with different loading modes and structural configurations. It was found that the inhomogeneous shear strain S13 is the key to the potential change in the PS shell structure. The emergence of the potential barriers and wells in the shell structure of PS is well explained. In addition, the position of the potential barriers can be modulated by varying the magnitude of the load, which provides a reference for the design of thin-film devices.

Torque‐tuned I‐V characteristics in a piezoelectric semiconductor composite fiber

AbstractThis paper studies the multi‐physical fields in a torsional composite fiber composed of a non‐piezoelectric semiconductor (PS) core coated with a piezoelectric dielectric shell. Based on the three‐dimensional framework of piezoelectricity and drift‐diffusion theory, we develop a nonlinear one‐dimensional model that incorporates the warping deformation, shear deformation, and axial variations of the electric field and charge transportations. A One‐dimensional model is linearized for small perturbations of charges, and we obtain the analytical solutions for single rods or PN junctions when torques are applied, which explicitly illustrates the electromechanical fields and redistribution of mobile charges. We also examine how the thickness of the composite rods affects the interaction between the piezoelectric and semiconductor components in the model. The optimal thickness ratio for maximizing the overall mobility of carriers has been discovered. This enables us to modify the thickness ratio to achieve the greatest PS interaction performance. Based on the nonlinear equations, we analyze the relationships between electric currents and applied voltages on the end of rods. Finally, we examine how twisting moments influence the characteristics of this I‐V relationship. The presented study provides a potential application for mechanical switches or sensors for PSs.

Abstract 490: Significant anti-proliferative effects of targeted magnetoelectric nanoparticles as potential theragnostic tools

Abstract Although current electroporation therapies have been demonstrated to be effective not only in ablating tumor tissue, but also in eliciting an anti-tumor immune response, they are limited in their application due to the strong risk factors associated with the high voltages required. Current methods of interacting with the body’s electrical currents are limited to traditional electrodes, which cause damage to surrounding tissue upon insertion, and require high voltages to create responses at the cellular level. Recent efforts at non-invasive interaction with the body’s electric fields have led to the fabrication of magnetoelectric nanoparticles (MENPs), a novel technology which has the ability to convert harmless magnetic fields into strong local electric fields, all while maintaining a diameter of ~70nm. These particles have been demonstrated to trigger neuronal firing under magnetic stimulation both in vitro and in vivo, and have been able to release chemotherapeutic agents on command in vitro and in vivo. This demonstrates the ability for MENPs to wirelessly generate electric fields within the body on demand with high temporal and spatial resolution. This suggests the potential for non-invasive electroporation therapy which could be triggered by external magnetic fields. Given the particles are themselves magnetic, this could show potential as a theragnostic tool as their magnetic properties suggest they may act simultaneously as an MRI contrast and an ablative therapy. To explore this possibility, we fabricated MENPs consisting of a magnetostrictive CoFe2O4 spinel core coupled with a piezoelectric BaTiO3 perovskite shell. These particles were then PEGylated to reduce agglomeration which is typical of magnetic nanoparticles. 50ul of a 1mg/ml PEG-MENP dispersion was deposited into a cell culture of SKOV-3 ovarian cancer cells. These cells were then stimulated by 120 10ms pulses of a 2kOe magnetic field over the course of 30 minutes. An cell-titre glo ATP assay was performed to indicate viability 24 hours after treatment. Treatment wells were compared to controls of no intervention, magnetic stimulation with no particles, and particles with no stimulation. The combination of particles and magnetic stimulation was the only group which showed significant decreases in viability, with a 32% reduction in viability. Particles on their own showed no effect on cell viability, neither did magnetic-only stimulation. This preliminary investigation into the use of MENPs as a non-invasive cancer treatment has shown some potential. The ability to wirelessly activate the particles provides an inherent targeting mechanism not found in traditional chemotherapeutics, while the nanometer diameter provides a non-invasive method to generate strong electric fields within the body. Citation Format: Max Shotbolt, Elric Zhang, Emily Zhu, Wael El-Rifai, John Bryant, Ping Liang, Sakhrat Khizroev. Significant anti-proliferative effects of targeted magnetoelectric nanoparticles as potential theragnostic tools [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 490.

Multiphysics simulation of magnetoelectric micro core-shells for wireless cellular stimulation therapy via magnetic temporal interference.

This paper presents an innovative approach to wireless cellular stimulation therapy through the design of a magnetoelectric (ME) microdevice. Traditional electrophysiological stimulation techniques for neural and deep brain stimulation face limitations due to their reliance on electronics, electrode arrays, or the complexity of magnetic induction. In contrast, the proposed ME microdevice offers a self-contained, controllable, battery-free, and electronics-free alternative, holding promise for targeted precise stimulation of biological cells and tissues. The designed microdevice integrates core shell ME materials with remote coils which applies magnetic temporal interference (MTI) signals, leading to the generation of a bipolar local electric stimulation current operating at low frequencies which is suitable for precise stimulation. The nonlinear property of the magnetostrictive core enables the demodulation of remotely applied high-frequency electromagnetic fields, resulting in a localized, tunable, and manipulatable electric potential on the piezoelectric shell surface. This potential, triggers electrical spikes in neural cells, facilitating stimulation. Rigorous computational simulations support this concept, highlighting a significantly high ME coupling factor generation of 550 V/m·Oe. The high ME coupling is primarily attributed to the operation of the device in its mechanical resonance modes. This achievement is the result of a carefully designed core shell structure operating at the MTI resonance frequencies, coupled with an optimal magnetic bias, and predetermined piezo shell thickness. These findings underscore the potential of the engineered ME core shell as a candidate for wireless and minimally invasive cellular stimulation therapy, characterized by high resolution and precision. These results open new avenues for injectable material structures capable of delivering effective cellular stimulation therapy, carrying implications across neuroscience medical devices, and regenerative medicine.

Electroelastic effects on local-global buckling of piezoelectric cylindrical shells with stepped thickness

Electroelastic effects on local-global buckling of piezoelectric cylindrical shells with stepped thickness

Mechanically induced electric potential and charge redistribution in laminated composite piezoelectric semiconductor circular cylindrical thin shells

We study electromechanical effects and piezotronic behaviors in a Kirchhoff–Love laminated composite piezoelectric semiconductor circular cylindrical thin shell, which is composed of a non-piezoelectric semiconductor core and two piezoelectric dielectric layers. A second-order assumption for electric potentials and carrier concentration perturbations is utilized to capture accurate descriptions of the electric field and charge distributions within the composite shell, where the zeroth-order, first-order, and second-order forms represent constant, antisymmetric, and symmetric distributions along the thickness, respectively. The field equations and boundary conditions are simultaneously derived through a principle of virtual work and the fundamental lemma of the calculus of variation. The new governing equations derived show a new coupling relation between mechanical deformation and charge behavior in the composite shell, where all mechanical deformations (extension, bending of the shell) and all distribution forms of electric potential (zeroth-, first-, second-order electric potentials) are coupled, which is different from piezoelectric semiconductor beams and plates. Then, the numerical results of electromechanical effects and piezotronic behaviors in static bending and forced vibration problems of the shell are conducted with the derived theoretical model. Numerical studies of static bending graphically show some fundamental coupling relations between mechanical forces and charge distributions in deformed piezoelectric semiconductor shells. The new results from the forced vibration analysis given by the current model show that the deflection amplitude and the electric potential distribution in the thin shell are frequency-dependent and can be adjusted by controlling the excitation frequency. In addition, the semiconducting properties (dependence of mechanical behavior on doping level) are studied in both static and dynamic problems. The mechanically controlled charge distribution suggests that shell-shaped piezoelectric semiconductor shells could serve as an effective means of sensing or energy harvesting by converting mechanical energy into electricity.

Static bending and forced vibration analyses of a piezoelectric semiconductor cylindrical shell within first-order shear deformation theory

This paper examines the mechanically induced electric potential and charge redistribution in a piezoelectric semiconductor cylindrical shell employing first-order shear deformation theory. The two-dimensional governing equations and corresponding boundary conditions are simultaneously derived through a principle of virtual work method and the fundamental lemma of the calculus of variation. For the application of electronic devices, static bending and forced vibration analyses of an open cylindrical shell under locally distributed normal forces are analytically solved with the derived theoretical model. The effects of doping level on electric potentials and mechanical displacements are presented. An interesting result shows that doping levels can alter the peak position of the zeroth-order electric potential. In addition, the first three order natural frequencies of the shell under time-harmonic load are identified, and the doping level is found to have an inhibiting effect on the first natural frequency. All the numerical results are beneficial for optimizing the design and performance of cylindrical shell-shaped sensors and energy harvesters.

Nonlinear free vibration of piezoelectric semiconductor doubly-curved shells based on nonlinear drift-diffusion model

Nonlinear free vibration of piezoelectric semiconductor doubly-curved shells based on nonlinear drift-diffusion model

Magnetoelectric nanoparticles shape modulates their electrical output.

Core-shell magnetoelectric nanoparticles (MENPs) have recently gained popularity thanks to their capability in inducing a local electric polarization upon an applied magnetic field and vice versa. This work estimates the magnetoelectrical behavior, in terms of magnetoelectric coupling coefficient (αME), via finite element analysis of MENPs with different shapes under either static (DC bias) and time-variant (AC bias) external magnetic fields. With this approach, the dependence of the magnetoelectrical performance on the MENPs geometrical features can be directly derived. Results show that MENPs with a more elongated morphology exhibits a superior αME if compared with spherical nanoparticles of similar volume, under both stimulation conditions analyzed. This response is due to the presence of a larger surface area at the interface between the magnetostrictive core and piezoelectric shell, and to the MENP geometrical orientation along the direction of the magnetic field. These findings pave a new way for the design of novel high-aspect ratio magnetic nanostructures with an improved magnetoelectric behaviour.

A general electroelastic analysis of piezoelectric shells based on levy-type solution and eigenvalue-eigenvector method

Eigenvalue-Eigenvector approach as well as Levy type solution are used for electroelastic analysis of a doubly curved shell made of piezoelectric material based on a shear deformable model and piezoelasticity relations. The electroelastic governing equations are derived using virtual work principle. The solution is proposed for a Levy type boundary conditions with two simply-supported boundary conditions and two clamped ones. After derivation of the governing equations, a solution satisfying two simply supported boundary conditions is assumed to arrive a system of ordinary differential equations. The latest governing equations are solved using Eigenvalue-Eigenvector method to satisfy clamped-clamped boundary conditions. The distribution of displacements, rotations, electric potential, strain and stress is presented along the planar coordinate. Accuracy of the proposed solution is justified through comparison with results of previous papers.