Impact Of Mechanical Vibrations Research Articles

The impact of mechanical vibration at cathode on hydrogen yields in water electrolysis

This study investigates the utilization of mechanical vibration to enhance the hydrogen evolution reaction (HER) in electrolysis processes. By varying the force magnitude and frequency of mechanical vibration, significant improvements in HER efficiency were observed. Specifically, the mechanical vibration-assisted electrolysis with a hitting frequency of 3 hits per second and 157.2698 Kg. m−2 hitting force improved the HER current density by 128 % compared to untreated water electrolysis. Linear sweep voltammetry (LSV) data for the graphite electrode revealed a distinct reduction peak at 1 V, indicating a favorable electrochemical reduction reaction influenced by mechanical vibration. The frequency of mechanical vibration significantly impacted the LSV response, with variations in current values across different conditions. Mechanistically, mechanical vibration disrupted intermolecular forces, facilitating better electrode-bubble interactions and accelerating reaction kinetics. Additionally, changes in pH levels induced by mechanical vibration further enhanced HER efficiency. These results suggest that integrating mechanical vibration into electrolysis systems significantly improves HER performance, contributing to the advancement of more efficient and sustainable hydrogen production technologies, which are crucial for achieving net-zero emission targets.

Impact of cycling conditions on lithium-ion battery performance for electric vertical takeoff and landing applications

The development of better electrochemical energy storage systems has sparked significant interest in using Li-ion batteries for electric vertical takeoff and landing (eVTOL) applications. To ensure the optimal performance and safety of onboard batteries, their behavior under different charging/discharging protocols and environmental conditions must be understood. This paper presents a comprehensive evaluation of commercial Li-ion batteries for eVTOL applications, focusing on their responses to varying charging/discharging strategies and mechanical vibrations experienced during flight. Through controlled experiments, the effects of rapid cycling on battery performance were investigated, including effects on lifespan, capacity, and internal resistance. Additionally, the impact of mechanical vibrations on battery behavior was assessed to identify potential challenges for onboard batteries. The results of this study revealed intriguing insights into the interplay between temperature, vibration, and battery performance. This work contributes to the broader adoption of electric aerial transportation, promising a greener and safer future for urban mobility.

Performance of hybrid supercapacitors in the presence of mechanical vibrations for applications of micro-mobility

Supercapacitors (SCs) have always been regarded as a source of electrical energy storage confined to equipment requiring high power, and particularly high currents, for a few moments. Hybrid SCs characterized by increasingly higher energy densities have been gaining ground. The main advantages of such accumulators are long service life, a high number of cycles which drastically reduces the problem of recycling lithium cells and good operation even at low temperatures. One of the most underestimated aspects, but with an impact on the service life of accumulators, is the mechanical vibration behavior. In micro-mobility vehicles, the battery pack is often attached to the charter, which in turn is not sufficiently dampened for normal road surface conditions. The literature mainly analyses the variation of ESR (internal resistance) as a function of the received vibration dose. In the following work, the impact of mechanical vibrations on the various parameters of an equivalent electrical circuit is assessed using impedance spectroscopy, and how the variation of individual components can influence the performance of a micro-mobility vehicle battery. The reference vibration cycle was realized by sampling a real driving cycle on an electric scooter on various types of urban terrain and was replicated on various types of cells using a shaker.

Research Status and Prospect for Vibration, Noise and Temperature Rise-Based Effect of Food Transport Pumps on the Characteristics of Liquid Foods.

In the field of food processing, the processing of liquid foods has always played an important role. Liquid foods have high requirements for the processing environment and equipment. As the core equipment in liquid foods processing, food transport pumps are widely used in liquid foods production, processing and transportation. Most liquid foods are non-Newtonian and vulnerable to vibration, noise, and temperature rise produced by rotary motions of food transport pumps in operation, which can finally affect foods safety. Therefore, this review summarizes the impact of mechanical vibration, noise, and temperature rise on liquid food products, with the aim of ensuring food safety while designing a cleaner, safer and more reliable food transport pumps in the future.

Modeling and Flowsheet Simulation of Vibrated Fluidized Bed Dryers

Drying in fluidized beds is an important step in the production of powdered materials. Especially in the food and pharmaceutical industry, fluidized bed dryers are often vibrated to improve the drying process. In the current work, a continuous fluidized bed drying model is implemented in the novel, open-source flowsheet simulation framework Dyssol. The new model accounts for the hydrodynamic characteristics of all Geldart groups as well as the impact of mechanical vibration on the drying process. Distributed particle properties are considered by the model. Comprehensive validation of the model was conducted for a wide range of process parameters, different materials, dryer geometries and dimensions as well as the impact of vibration. Particle properties are predicted accurately and represent the broad experimental data well. A sensitivity analysis of the model confirmed grid independence and the validity of underlying model assumptions.

Studying the Dynamic Properties of a Distributed Thermomechanical Controlled Plant with Intrinsic Feedback. I

The dynamic properties of the response of a one-dimensional elastic system to an external thermal action are studied. In contrast to the author's previous publication on the properties of this plant, the impact of mechanical vibrations on the heat transfer process is also considered. As is established below, with this impact taken into account, the double integrating effect in the thermal action-to-mechanical vibrations channel still holds.

Monte Carlo Assessment of the Impact of Oscillatory and Pulsating Boundary Conditions on the Flow Through Porous Media

Stress and water injection induce deformations and changes in pore pressure in the soil. The interaction between the mechanical deformations and the flow of water induces a change in porosity and permeability, which results in nonlinearity. To investigate this interaction and the impact of mechanical vibrations and pressure pulses on the flow rate through the pores of a porous medium under a pressure gradient, a poroelastic model is proposed. In this paper, a Galerkin finite element method is applied for solving the quasi-static Biot’s consolidation problem for poroelasticity, considering nonlinear permeability. Space discretisation using Taylor–Hood elements is considered, and the implicit Euler scheme for time stepping is used. Furthermore, Monte Carlo simulations are performed to quantify the impact of variation in the parameters on the model output. Numerical results show that pressure pulses and soil vibrations in the direction of the flow increase the amount of water that can be injected into a deformable fluid-saturated porous medium.

Mechanical vibrations in welding processes

This article presents the current state of knowledge on the issue of supporting classic welding processes by mechanical vibrations. Selected results of own research on the impact of mechanical vibration on the structure and properties of welding structures are also discussed.

The Impact of Mechanical Vibration on the Hardening of Metallic Surface

One of functional parameters which have a big influence on the reliability of machine is the surface quality of mobile and immobile parts. The quality working ability of the surface in contact is depending of their surfaces strength. In this regard, we used vibro-mechanical treatment to increase the hardness of the contact surfaces which is considered as formed surface of plastic deformation. The formed plastic deformation surface is also a kind of micro relief surface, characterized by multitude closed and superimposed on each other traces of contact with the particles working environment cultivated surface. The quality of the surface resulting from the vibro-impact treatment, provide a sufficiently high wear parts. This paper presents experimental results of using the vibro-impact treatment on surface fatigue strength using samples of steels, aluminums and titans alloys. The objective of this study is to improve performance functional surfaces in contact by choosing optimal hardening parameters.

Impact of Mechanical Vibration on the Performance of RF MEMS Evanescent-Mode Tunable Resonators

This letter presents the first experimental investigation on the impact of mechanical vibration on the performance of MEMS evanescent-mode tunable resonators. It is shown both conceptually and experimentally that mechanical vibration can introduce distortions to the RF signal. Signal distortions are found to be very small (<; -40 dBc of sideband or <; 0.5% change in-error vector magnitude) for a diaphragm based MEMS tunable resonator with a diaphragm size of 7 × 7 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and mechanical vibration amplitude of 1g. A novel MEMS tunable evanescent-mode resonator based on two arrays of cantilever beams that replace the diaphragm is also presented to achieve even lower distortion in the presence of mechanical vibration. A 15-25 dB reduction in the vibration-induced sideband is observed.

Impact of Mechanical Vibrations on Laser Stability and Carrier Phase Estimation in Coherent Receivers

Coherent communication systems are largely limited by the laser linewidth of the local oscillator. In addition to phase noise, large frequency deviations can occur if the laser is mechanically vibrated. The detrimental effect of the frequency instability is measured for coherent optical receivers on a typical laser and numerically analyzed for quadrature phase-shift keying and 16-quadrature amplitude modulation using common feed-forward carrier phase recovery algorithms.

An analysis method for determining the head positioning error of hard disk drives-settling response analysis

A settling response analysis method for hard disk drives has been developed. In this method, the settling response is decomposed into its contributing modes using the Prony method, which is one of the experimental modal analysis methods. These modes are divided into servo modes and mechanical vibration modes based on the damping ratio in order to recompose a servo response and a mechanical vibration response. The impact of mechanical vibrations on settling response is quantified by their 2-norm. Relating to the track misregistration (TMR) budget design, each mechanical vibration mode is evaluated according to its initial amplitude and its decay rate.