Electroosmotic Effects Research Articles

Tribological performance of the micro-textured ceramic/superalloy interface under nanofluid minimum quantity lubrication considering electroosmotic effect

Tribological performance of the micro-textured ceramic/superalloy interface under nanofluid minimum quantity lubrication considering electroosmotic effect

Effects of Electroosmosis on Peristaltic Flow of Eyring-Powell Fluid Through a Non-Uniform channel: An Application to Blood flow

This study examines the electroosmotic effects of a non-uniform passage during the peristaltic phase of an Eyring-Powell model fluid. Understanding how the channel walls affect fluid flow issues in biofluid dynamics is the main goal of the study. Integrating the convective boundary conditions into the series perturbation paradigm is the main focus of the work, assuming low Reynolds number and a long wavelength. For temperature, velocity, stream function and concentration, the governing non-linear equations have their solutions found. MATLAB R2023a software is used to demonstrate a graphical presentation of the study's improvements in accessibility through parametric assessment. The research yields important insights, particularly regarding natural phenomena like blood flow in small arteries, which might be utilized for intervention or management in dysfunctional circumstances. As the analysis demonstrates, different viscosities also have a big role in boosting the temperature profiles, and electroosmotic parameters have a major impact on the fluid properties.

Simulation study on mitigating permeate flux decline with electroosmotic flux in dead-end ultrafiltration process

Piezoelectric membranes establish electrokinetic phenomena, including electroosmotic flow, to mitigate membrane fouling in the ultrafiltration process. This study employs numerical simulations to evaluate the role and impact of the electroosmotic flux effect on permeate flux decline and fouling mechanisms in the dead-end filtration process for silicon dioxide particles. This research demonstrates that electroosmotic flux significantly alleviates flux decline across varying values of surface zeta potential, membrane porosity, particle size and inlet concentration. Specifically, the electroosmotic flux effect is most pronounced in reducing flux decline when the surface zeta potential is higher and the membrane structure is more porous. This reduction in flux decline is attributed to the enhanced lift and drag forces generated by electroosmotic flux near the electrical double layer, which prevents rapid initial adhesion and subsequent fouling, such as internal blocking and cake layer formation. Additionally, the electroosmotic flux effect is most effective with smaller particle sizes and higher feed concentrations, helping to mitigate flux decline that would otherwise occur in the absence of electroosmotic flux. Compared to experimental and modelling investigations, the electroosmotic flux effect is shown to complement a reduction in permeate flux drop to facilitate the longevity of membranes in the ultrafiltration process.

Computational study on cilia transport of Prandtl nanofluid (blood-Fe3O4) enhancing convective heat transfer along microorganisms under electroosmotic effects in wavy capillaries

Purpose This study aims to focuse on the flow behavior of a specific nanofluid composed of blood-based iron oxide nanoparticles, combined with motile gyrotactic microorganisms, in a ciliated channel with electroosmosis. Design/methodology/approach This study applies a powerful mathematical model to examine the combined impacts of bio convection and electrokinetic forces on nanofluid flow. The presence of cilia, which are described as wave-like motions on the channel walls, promotes fluid propulsion, which improves mixing and mass transport. The velocity and dispersion of nanoparticles and microbes are modified by the inclusion of electroosmosis, which is stimulated by an applied electric field. This adds a significant level of complexity. Findings To ascertain their impact on flow characteristics, important factors such as bio convection Rayleigh number, Grashoff number, Peclet number and Lewis number are varied. The results demonstrate that while the gyrotactic activity of microorganisms contributes to the stability and homogeneity of the nanofluid distribution, electroosmotic forces significantly enhance fluid mixing and nanoparticle dispersion. This thorough study clarifies how to take advantage of electroosmosis and bio convection in ciliated micro channels to optimize nanofluid-based biomedical applications, such as targeted drug administration and improved diagnostic processes. Originality/value First paper discussed “Numerical Computation of Cilia Transport of Prandtl Nanofluid (Blood-Fe3O4) Enhancing Convective Heat Transfer along Micro Organisms under Electroosmotic effects in Wavy Capillaries”.

Numerical simulation of pulsatile flow of tangent hyperbolic fluid in a diseased curved artery with electro-osmotic effects

Numerical simulation of pulsatile flow of tangent hyperbolic fluid in a diseased curved artery with electro-osmotic effects

Single-Molecule Identification and Quantification of Steviol Glycosides with a Deep Learning-Powered Nanopore Sensor.

Steviol glycosides (SGs) are a class of high-potency noncalorie natural sweeteners made up of a common diterpenoid core and varying glycans. Thus, the diversity of glycans in composition, linkage, and isomerism results in the tremendous structural complexity of the SG family, which poses challenges for the precise identification and leads to the fact that SGs are frequently used in mixtures and their variances in biological activity remain largely unexplored. Here we show that a wild-type aerolysin nanopore can detect and discriminate diverse SG species through the modulable electro-osmotic flow effect at varied applied voltages. At low voltages, the neutral SG molecule was drawn and stuck in the pore entrance due to an energy barrier around R220 sites. The ensuing binding events enable the identification of the majority of SG species. Increasing the voltage can break the barrier and cause translocation events, allowing for the unambiguous identification of several pairs of SGs differing by only one hydroxyl group through recognition accumulation from multiple sensing regions and sites. Based on nanopore data of 15 SGs, a deep learning-based artificial intelligence (AI) model was created to process the individual blockage events, achieving the rapid, automated, and precise single-molecule identification and quantification of SGs in real samples. This work highlights the value of nanopore sensing for precise structural analysis of complex glycans-containing glycosides, as well as the potential for sensitive and rapid quality assurance analysis of glycoside products with the use of AI.

A computational investigation for heat and fluid transport with electro-osmosis phenomenon in a scraped surface heat exchanger

Scraped surface heat exchangers (SSHEs) have prominently shown their eminence in various food, chemical and in pharmaceutical industries when the regular processing of fluids and pertinent materials is encountered. The heat transfer analysis of Williamson fluid flow with electro osmotic effects in a narrow-gap SSHE is designed by implementing constant temperature difference between the gaps of the rotor and the stator. A fluid model is established by using lubrication approximation theory and Debye-Huckel simplifications. The computational solution is elaborated by implementing renowned BVP4C technique in MATLAB. Exact solution of Poisson-Boltzmann equation for different scenarios of SSHE is gathered, whereas solution for velocity, stream functions and temperature in various parts of SSHE are explored computationally. Impact of various crucial physical flow parameters like, Weissenberg number, mobility of the medium number, electro osmotic parameter on the velocity profile, stream function, temperature profile, and pressure gradient has been explored graphically. The numerical solution is compared with artificial neural network (ANN) and an absolute alignment of BVP4C solution is observed with ANN solution. It is reported that fluid flow is lifted with enhancing the viscoelastic behavior and exhibits dual behavior for electroosmosis phenomenon and mobility of medium parameter. Also, it is seen that temperature of the fluid is significantly declines with Weissenberg number and is surges with enhancing mobility of medium and Brinkman number. By increasing the Brinkman number conduction phenomenon is slow down and heat produced due to viscous dissipation, raises the temperature of the fluid. The viscoelastic effect could be of enormous significance in applications, like Polymer processing in certain heat exchangers, and in mixing and blending foodstuffs etc.

Electroosmotic effect on the flow of hybrid nanofluid containing para and ferri-magnetic nanoparticles through the micro-channel implementing Darcy law

This study investigates the flow of an incompressible electroosmotic hybrid nanofluid through a micro-channel. The hybrid nanofluid consists of paramagnetic (Ta) and ferrimagnetic (Fe3O4) nanoparticles suspended in ethylene glycol. The Darcy model is applied to the porous media in the momentum equation, and its effects are also considered in the temperature equation, accounting for frictional and Joule heating effects. The micro-channel is influenced by both pressure and magnetic flux. The study derives an exact solution for the proposed model and evaluates key engineering parameters, such as the heat transfer rate. The findings show that a higher particle volume fraction reduces the velocity distribution, while an increased Darcy parameter decreases the rate of heat transfer. Additionally, the heat transfer rate diminishes with increasing Darcy parameter and electric flux. Notably, the ferrimagnetic nanofluid exhibits better thermal conductivity than the paramagnetic nanofluid.

In-tube micro-pyramidal silicon nanopore for inertial-kinetic sensing of single molecules

Electrokinetic force has been the major choice for driving the translocation of molecules through a nanopore. However, the use of this approach is limited by an uncontrollable translocation speed, resulting in non-uniform conductance signals with low conformational sensitivity, which hinders the accurate discrimination of the molecules. Here, we show the use of inertial-kinetic translocation induced by spinning an in-tube micro-pyramidal silicon nanopore fabricated using photovoltaic electrochemical etch-stop technique for biomolecular sensing. By adjusting the kinetic properties of a funnel-shaped centrifugal force field while maintaining a counter-balanced state of electrophoretic and electroosmotic effect in the nanopore, we achieved regulated translocation of proteins and obtained stable signals of long and adjustable dwell times and high conformational sensitivity. Moreover, we demonstrated instantaneous sensing and discrimination of molecular conformations and longitudinal monitoring of molecular reactions and conformation changes by wirelessly measuring characteristic features in current blockade readouts using the in-tube nanopore device.

Electroosmotic peristaltic flow of thixotropic-Newtonian fluids in a circular tube: Effect of variable viscosity co-efficient of core fluid

In this article, the behaviour of peristaltic motion of two-phase immiscible fluids under the influence of an external electric field is investigated. The core fluid (thixotropic) is deliberated as a variable viscosity attribute which is surrounded by Newtonian fluid. Meanwhile, both fluids possess electrical conductivity in nature. This analysis was carried out under certain physical restrictions, namely, Debye–hückel linearization, a very thin electric double layer effect at the wall area, low Reynolds number and long wavelength approximation. The interface analysis was computed and higher resistance was noticed in the power-law index and variable viscosity components and lower resistance in the electrokinetic body force. Moreover, the present study also evaluates the characteristics of pressure rise, the influence of variable viscosity and the electroosmotic effect on the mechanical efficiency and wall shear stress. The vanishing moments of trapping phenomena were spotted when the magnitude of the electroosmotic effect and structural parameter increased. The present model is the generalized form of the power-law – Newtonian model and Newtonian–Newtonian model. These resultant outcomes may be fruitful for the modulation of pumping in a physical environment in the presence of an external electric field and variable viscosity.

Electro-osmotic Flow Generation via a Sticky Ion Action.

Selective transport of ions through nanometer-sized pores is fundamental to cell biology and central to many technological processes such as water desalination and electrical energy storage. Conventional methods for generating ion selectivity include placement of fixed electrical charges at the inner surface of a nanopore through either point mutations in a protein pore or chemical treatment of a solid-state nanopore surface, with each nanopore type requiring a custom approach. Here, we describe a general method for transforming a nanoscale pore into a highly selective, anion-conducting channel capable of generating a giant electro-osmotic effect. Our molecular dynamics simulations and reverse potential measurements show that exposure of a biological nanopore to high concentrations of guanidinium chloride renders the nanopore surface positively charged due to transient binding of guanidinium cations to the protein surface. A comparison of four biological nanopores reveals the relationship between ion selectivity, nanopore shape, composition of the nanopore surface, and electro-osmotic flow. Guanidinium ions are also found to produce anion selectivity and a giant electro-osmotic flow in solid-state nanopores via the same mechanism. Our sticky-ion approach to generate electro-osmotic flow can have numerous applications in controlling molecular transport at the nanoscale and for detection, identification, and sequencing of individual proteins.

Perturbation solution of multiphase flow of Williamson fluid through convergent and divergent conduits: Electro-osmotic effects

Problem Statement: The hafnium particles are suspended through carrier fluid (Williamson fluid) to discuss the momentum analysis in multiphase flow in two different types of configurations. Research gap: The analysis of the interaction of hafnium nanoparticles with the Williamson fluid model through the convergent and divergent conduits has not been discussed before. Methodology: The equation of continuity and momentum equations are used for this analysis. The solution of both fluid and particle velocities is obtained through the perturbation analytical technique. The perturbation solution is also compared with the numerical solution. Computational results: The Weissenberg number decays the velocity distribution. The suspension of hafnium particles updates the flow distribution through the conduits. The magnitude of the stream function decreases via the Weissenberg number. Applications: This study can help develop a new approach to cancer therapy by using a high atomic number of nanoparticles. Originality: This analysis is original and has neither been submitted nor published before.

Electroosmotic and Gyrotactic Microorganisms Effects on MHD Al2O3-Cu/Blood Hybrid Nanofluid Flow through Multi-Stenosed Bifurcated Artery.

The purpose of this study is to investigate the electroosmotic flow of a hybrid nanofluid (Al2O3-Cu/Blood) with gyrotactic microorganisms through a bifurcated artery with mild stenosis in both parent and daughter arteries. The flow is subjected to a uniform magnetic field, viscous dissipation, and a heat source. The governing equations undergo the non-dimensional transformation and coordinate conversion to regularize irregular boundaries, then solve the resulting system using the Crank-Nicolson method. In both sections of the bifurcated artery (parent and daughter artery), the wall shear stress (WSS) profile decreases with increasing stenotic depth. Nusselt profile increases with an increase in the heat source parameter. The present endeavour can be beneficial for designing better biomedical devices and gaining insight into the hemodynamic flow for therapeutic applications in the biomedical sciences.

Thermal and mass exchange in a multiphase peristaltic flow with electric-debye-layer effects and chemical reactions using machine learning

The present investigation delves into the analysis of mass and thermal transmission during the peristalsis of a two phase flow of a Prandtl fluid, within a symmetric channel by considering entropy generation and minimization. The considered flow is examined by taking into account the impacts of electroosmotic effects through Electric Debye Layer (EDL) and chemical reactions followed by the lubrication theory approximation. Numerical solutions are acquired for the consequential differential equations through artificial neural networks (ANN) based fitness functions. The artificial neural networks (ANN) based fitness function optimized through hybrid evolutionary algorithms especially ABC (artificial bee colony) and NNA (neural network algorithm) like ANN-ABC-NNA. For the efficiency and validation of the algorithm we conduct the one hundred (100) independent runs. The obtained results through ANN-ABC-NNA are compared with the exact solutions for validation of results. In the present examination, the velocity profile is noticed to increase by the rise in the electroosmotic factor and solid particles concentration, while it decreases for the Prandtl fluid parameter. This research holds practical significance in diverse applications, particularly in the design and optimization of microfluidic devices.

Dynamic transport characteristics and performance response of commercial-size polymer electrolyte membrane fuel cell stack: An experimental study

The stability and durability of polymer electrolyte membrane fuel-cell stacks are closely related to their dynamic performance responses and internal transport characteristics, particularly for commercial-size stacks in automotive applications. In this study, the dynamic behaviors of a 10-cell stack (active area: 310 cm2) are investigated under various loading/unloading processes and cathode stoichiometric ratios; additionally, the joint influence of these two factors is analyzed. Voltage hysteresis is observed, and the dominant roles of dynamic oxygen, membrane water, and liquid transport are elucidated. The results indicate that the electro-osmotic effect dominates and results in anode-membrane dehydration as the loading process proceeds (>1.5 A cm−2). A larger airflow velocity enables faster downstream oxygen delivery, causing the oxygen concentration to reduce initially and then increase gradually with time after loading, thus voltage undershoots appear. Voltage hysteresis is enabled during the continuous loading/unloading/loading process owing to the difference in accumulated liquid water drainage ability after step loading and unloading. Although the synergistic loads and cathode stoichiometric ratio variations enable less cell-performance deterioration than that on contrary strategy, the dynamic characteristics are much more unstable and more likely to induce cell-stack failure and durability problems. This study provides insights into the dynamic transport characteristics in a commercial-size fuel cell stack and presents a guidance for control strategy development.

Effects of joule heating and viscous dissipation on electromagneto-hydrodynamic flow in a microchannel with electroosmotic effect: Enhancement of MEMS cooling

This paper inspects the effect of Joule heating and viscous dissipation due to electric double layer (EDL) and electroosmotic effect on steady fully developed electromagnetohydrodynamic flow in a microchannel. Dimensionless formulations of the Poisson-Boltzmann, momentum, and energy equations are derived for the electric potential, velocity profile, and temperature distribution in the microchannel. Exact solutions for the temperature distributions and velocity profile were obtained using the method of undetermined coefficients. The Debye-Hückel linearization is used to get exact solution for the electric potential. The results showed that Brinkmann number [Formula: see text], Joule heating parameter [Formula: see text], Debye-Hückel parameter [Formula: see text], Hartmann number [Formula: see text], and electric field [Formula: see text] have a substantial impact on flow formation and heat transfer. The complex interaction between joule heating, viscous dissipation, and the EOF effect were accurately captured. The range values for the governing parameter for [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] are [Formula: see text], and[Formula: see text] respectively.

Investigating of electro-osmotic flow effects due to electrical stimulation therapy using computational fluid dynamics

Investigating of electro-osmotic flow effects due to electrical stimulation therapy using computational fluid dynamics

Electrohydrodynamic peristaltic microfluidic flow with thermal and molecular analysis featuring sloped configurations

This study examines the simultaneous impacts of thermal and molecular transfer of non-Newtonian fluid propelled by the collective impact of electroosmosis and peristaltic pumping via inclined channel. Internal frictional heating and heat generation are also taken into consideration. The electrohydrodynamic phenomenon is described by the nonlinear Poisson–Boltzmann equation. The problem is modulated mathematically through a system of coupled non-linear differential equations in wave frame of reference. Using the regular perturbation method around a small wave number δ, we obtain sequential solutions for stream function ψ, electric potential ϕ, velocity u, pressure gradient dpdx, temperature θ and concentration Ω distributions. The influences of newly arising parameters such as the electroosmotic parameter me, relaxation time parameter λ1, retardation time parameter λ2, wave number δ, Reynold’s number Re, heat generation parameter β, Prandtl number Pr, Schmidt number Sc, Froude number Fr and Soret number Sr on physical characteristics are analyzed graphically. There is an inverse correlation between the parameters of relaxation time and retardation time and their effects on axial velocity, concentration, and temperature distributions. In particular, the temperature of the fluid increases as the EDL parameter, relaxation time parameter, viscous dissipation parameter, and Reynolds number increase, but decreases as the retardation time parameter increases. Moreover, the axial pressure gradient increases as Reynolds number and inclination angle increase, while it decreases as Froude number increases. The current model has applicability in the chemical industry, reservoir engineering, micro-fabrication, and biomedical applications, where electroosmotic effects on heat and mass movement are crucial.

Fast and Strong Carbon Nanotube Yarn Artificial Muscles by Electro-osmotic Pump.

Previous electrochemically powered yarn muscles cannot be usefully operated between extreme negative and extreme positive potentials, since generated stresses during anion injection and cation injection partially cancel because they are in the same direction. We here report an ionomer-infiltrated hybrid carbon nanotube (CNT) yarn muscle that shows unipolar stress behavior in the sense that stress generation between extreme potentials is additive, resulting in an enhanced stress generation. Moreover, the stress generated by this muscle unexpectedly increases with the potential scan rate, which contradicts the fact that scan-rate-induced stress decreases for neat CNT muscles. It is revealed by the electro-osmotic pump effect that the effective ion size injected into the muscle increases with an increase in the scan rate. We demonstrate an electrochemically powered gel-elastomer-yarn muscle adhesive that generates and delivers muscle-contraction-mimicking stimulation to a target tissue.

Role of suction/injection on electromagnetohydrodynamics natural convection flow in a porous microchannel with electroosmotic effect

This paper examined the role of suction/injection on time-dependent electromagnetohydrodynamics (EMHD) natural (free) convection flow in a vertical microchannel with electroosmotic effect. With the aid of Laplace transformation method, the governing energy and momentum equations are converted from partial differential equation (PDE) into ordinary differential equation (ODE) to obtain fluid temperature and velocity in Laplace domain. The semi-analytical solutions of the velocity profile and temperature distribution have been derived using the Riemann sum approximation. After which a MATLAB program was written to study the effects of Prandlt number Pr, Hartmann number Ha, electric field strength on x and z directions (Ex and Sz) and Grashof number Gr in fluid velocity, temperature, skin-friction and mass flow rate in terms of line graphs. Result shows the role of suction/injection parameter alters the temperature distribution and velocity profile, so also how effective the governing parameters contribute to the flow formation. .