Extension of the Crawley’s adhesive model to dynamically actuated piezoelectric transducers

In this article, the analysis of the acoustic path during the ultrasonic pulse echo testing of the rail head in production is carried out. The influence of the parameters of the applied piezoelectric transducers on the distribution of sensitivity for the sounding scheme used in the existing installations is estimated and the real sensitivity of detecting defects of the «non-metallic inclusion» type is estimated.

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Piezoelectric Energy Harvesting Solutions: A Review

Sensors ◽

10.3390/s20123512 ◽

2020 ◽

Vol 20 (12) ◽

pp. 3512 ◽

Cited By ~ 12

Author(s):

Corina Covaci ◽

Aurel Gontean

Keyword(s):

Energy Harvesting ◽

Piezoelectric Effect ◽

Piezoelectric Transducers ◽

Piezoelectric Energy Harvesting ◽

Piezoelectric Energy ◽

Direct Piezoelectric Effect ◽

Harvesting Technique ◽

Different Shapes ◽

Piezoelectric Devices ◽

Review Current

The goal of this paper is to review current methods of energy harvesting, while focusing on piezoelectric energy harvesting. The piezoelectric energy harvesting technique is based on the materials’ property of generating an electric field when a mechanical force is applied. This phenomenon is known as the direct piezoelectric effect. Piezoelectric transducers can be of different shapes and materials, making them suitable for a multitude of applications. To optimize the use of piezoelectric devices in applications, a model is needed to observe the behavior in the time and frequency domain. In addition to different aspects of piezoelectric modeling, this paper also presents several circuits used to maximize the energy harvested.

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Impedance Spectroscopy of Lead-Free Ferroelectric Coatings

Coatings ◽

10.3390/coatings11020221 ◽

2021 ◽

Vol 11 (2) ◽

pp. 221

Author(s):

Mariya Aleksandrova ◽

Ivailo Pandiev

Keyword(s):

Composite Coatings ◽

Electrical Circuit ◽

Ferroelectric Materials ◽

Piezoelectric Transducers ◽

Lead Free ◽

Electrical Behavior ◽

Oxide Composite ◽

Before And After ◽

Frequency Dependences ◽

Good Agreement

This paper presents impedance measurements of ferroelectric structures involving lead-free oxide and polymer-oxide composite coatings for sensing and energy harvesting applications. Three different ferroelectric materials grown by conventional microfabrication technologies on solid or flexible substrates are investigated for their basic resonant characteristics. Equivalent electrical circuit models are applied to all cases to explain the electrical behavior of the structures, according to the materials type and thickness. The analytical results show good agreement with the experiments carried out on a basic types of excited thin-film piezoelectric transducers. Additionally, temperature and frequency dependences of the dielectric permittivity and losses are measured for the polymer-oxide composite device in relation with the surface morphology before and after introduction of the polymer to the functional film.

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A phononic interface between a superconducting quantum processor and quantum networked spin memories

npj Quantum Information ◽

10.1038/s41534-021-00457-4 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Tomáš Neuman ◽

Matt Eichenfield ◽

Matthew E. Trusheim ◽

Lisa Hackett ◽

Prineha Narang ◽

...

Keyword(s):

Quantum State ◽

Piezoelectric Transducers ◽

High Fidelity ◽

Hybrid Architecture ◽

Quantum Networks ◽

Superconducting Circuit ◽

Artificial Atom ◽

Experimental Parameters ◽

Quantum Processor ◽

State Spin

AbstractWe introduce a method for high-fidelity quantum state transduction between a superconducting microwave qubit and the ground state spin system of a solid-state artificial atom, mediated via an acoustic bus connected by piezoelectric transducers. Applied to present-day experimental parameters for superconducting circuit qubits and diamond silicon-vacancy centers in an optimized phononic cavity, we estimate quantum state transduction with fidelity exceeding 99% at a MHz-scale bandwidth. By combining the complementary strengths of superconducting circuit quantum computing and artificial atoms, the hybrid architecture provides high-fidelity qubit gates with long-lived quantum memory, high-fidelity measurement, large qubit number, reconfigurable qubit connectivity, and high-fidelity state and gate teleportation through optical quantum networks.

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CFD-DEM Simulation of Spouted Bed Dynamics under High Temperature with an Adhesive Model

Energies ◽

10.3390/en14082276 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2276

Author(s):

Zhao Chen ◽

Lin Jiang ◽

Mofan Qiu ◽

Meng Chen ◽

Rongzheng Liu ◽

...

Keyword(s):

High Temperature ◽

Particle Surface ◽

Particle Collision ◽

Gas Velocity ◽

Spouted Bed ◽

Dem Simulation ◽

Linear Spring ◽

Adhesion Model ◽

Adhesive Model ◽

Damping Model

Particle adhesion is of great importance to coating processes due to its effect on fluidization. Currently, Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) has become a powerful tool for the study of multiphase flows. Various contact force models have also been proposed. However, particle dynamics in high temperature will be changed with particle surface properties changing. In view of this, an adhesion model is developed based on approaching-loading-unloading-detaching idea and particle surface change under high temperature in this paper. Analyses of the adhesion model are given through two particle collision process and validated by experiment. Effects of inlet gas velocity and adhesion intensity on spouted bed dynamics are investigated. It is concluded that fluidization cycle will be accelerated by adhesion, and intensity of fluidization will be marginally enhanced by slight adhesion. Within a certain range, increasing inlet gas velocity will lead to strong intensity of particle motion. A parameter sensitivity comparison of linear spring-damping model and Hertz-Mindlin Model is given, which shows in case of small overlaps, forces calculated by both models have little distinction, diametrically opposed to that of large overlaps.

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Assessment of Piezoelectric Sensors for the Acquisition of Steady Melt Pressures in Polymer Extrusion

Fluids ◽

10.3390/fluids4020066 ◽

2019 ◽

Vol 4 (2) ◽

pp. 66

Author(s):

Sónia Costa ◽

Paulo Teixeira ◽

José Covas ◽

Loic Hilliou

Keyword(s):

Polymer Processing ◽

Piezoelectric Transducers ◽

Piezoelectric Sensors ◽

Flow Curves ◽

Signal Drift ◽

Temperature And Pressure ◽

Pressure Independent ◽

Pressure Changes ◽

Different Levels ◽

Slit Die

Piezoelectric sensors have made their way into polymer processing and rheometry applications, in particular when small pressure changes with very fast dynamics are to be measured. However, no validation of their use for steady shear rheometry is available in the literature. Here, a rheological slit die was designed and constructed to allow for the direct comparison of pressure data measured with conventional and piezoelectric transducers. The calibration of piezoelectric sensors is presented together with a methodology to correct the data from the inherent signal drift, which is shown to be temperature and pressure independent. Flow curves are measured for polymers showing different levels of viscoelasticity. Piezoelectric slit rheometry is validated and its advantage for the rheology of thermodegradable materials with viscosity below 100 Pa·s is highlighted.

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