Slanted Field Research Articles

Fast-response liquid crystal display device with trapezoidal pixel electrodes

ABSTRACT A fast response liquid crystal display (LCD) with trapezoidal pixel electrodes is proposed. The trapezoidal shape of the pixel electrode generates a slanted electric field, eliminating the need for a non-zero pre-tilt angle to prevent random domain formation in the LC. Additionally, the absence of a pre-tilt angle enhances viewing angles. During operation, LC molecules can form virtual walls, increasing anchoring energy and improving response time. At 38% transmittance, the response time is 5.1 ms, while at 60% transmittance, it increases to 8.3 ms. With a circular polariser, the device achieves a contrast ratio of 200:1 and a viewing cone of approximately 18°. Consequently, the trapezoidal pixel electrode FFS cell is suitable for fast LCDs used in automotive displays and digital signage. Its narrow viewing angles with a circular polariser also make it ideal for personal privacy displays and certain mobile displays.

Hydromagnetic Convective Heat Transfer in a Square Cavity Filled with Fe3O4-Water Nanofluid Saturated Porous Medium

A numerical study is carried out to demonstrate the heat transmission events of nanofluid in a square cavity saturated by aluminum foam porous medium under the effect of slanted periodic magnetic field. The cavity wall is heated from left and cooled from right while horizontal walls are supposed to be adiabatic. The Brownian motion of nanoparticle is taken into consideration in the thermal conductivity model construction. The dimensionless governing equations including Darcy-Brinkman model are solved by Galerkin-FEM. The outcomes are exposed with depictions of streamlines, isotherms and average Nusselt numbers. The numerical investigation is performed for parameters: Darcy number, Rayleigh number, Hartmann number, porosity, leaning angle of the periodic magnetic field, period number, and nanoparticle volume fraction. The heat transfer rate upsurges noticeably for the rise of nanoparticle volume fraction, period number, Darcy number and Rayleigh number but the reverse trend is found for the parameter Hartmann number as well as porosity. From the acquired numerical outcomes, the maximum rate of heat transfer is attained at δ=π/4 when λ = 1. Jagannath University Journal of Science, Volume 10, Number II, Dec. 2023, pp. 145-158

Heat Transfer Characteristics of Al2O3-Cu/Water Hybrid Nanofluid inside a Square Cavity in the Presence of Inclined Periodic Magnetic Field

The goal is to scrutinize the thermal features of hybrid nanofluid in a square cavity with the effect of oblique periodic magnetic field. The modified hybrid nanofluid is a combination of nanoparticles , and base fluid water with equal volume fraction of and The finite element method based Galerkin weighted residual scheme is chosen to find the solution of the non-dimensional governing equations. The effects of different model factors such as oblique angle and period of the periodic magnetic field, Hartmann number, Rayleigh number, nanoparticles volume fraction on the heat transfer are scrutinized. The outcomes are exhibited with the help of isotherms and average Nusselt number as well. The numerical results show that when the period of the slanted periodic magnetic field increases gradually, the distinct model factors (Rayleigh number, nanoparticles volume fraction, and slanting angle) raise the heat transfer rate progressively, whereas augmentation of the Hartmann number diminutions the entire heat transfer rate. Jagannath University Journal of Science, Volume 10, Number II, Dec. 2023, pp. 75-86

Thin film Weyl semimetals with turning number of Fermi surface greater than unity

The development of Weyl semimetals (WSMs) as a new type of quantum material for a variety of novel phenomena is underway. In this context WSM with broken time reversal symmetry and inversion symmetry confined to a thin film which exhibits topologically distinct Fermi surface in the low energy regime is presented. The equi-energy contours possess a topological invariant called turning number ν. We extend the numerical investigation of the magnetotransport in the WSM to include systems with the turning number of Fermi surface greater than unity, ν=2, which is due to the self intersection of equi-energy contours. This results in exotic Weyl orbits which are a hybrid of bulk and surface states and are crucial for magnetotransport. This is in contrast to the conventional electron gas in which orbits are closed curves without self intersection. The contour of Weyl orbits in real space is connected to the shape of Fermi surface. In the presence of a perpendicular magnetic field on a slab geometry, the probability density of edge states are wide and narrow on each edge rather than symmetric on both edges (the hall mark of conventional quantum Hall effect). We explore the effect of disorder on these asymmetric edge states and find that the conductance remains quantized at 2e2/h up to a critical disorder strength. Our findings show that the transport characteristics of WSM are more robust to disorder in a particular direction for these systems with higher turning number. These systems also show unusual conductance by a slanted magnetic field as the slant can modify the Landau levels at the Fermi level.

LSM analysis of thermal enhancement in KKL model-based unsteady nanofluid problem using CCM and slanted magnetic field effects

LSM analysis of thermal enhancement in KKL model-based unsteady nanofluid problem using CCM and slanted magnetic field effects

Effect of Temperature Gradient Dependent Heat Source, Secondary Velocity on Mixed Convective Flow of Nanofluid through Non-Darcy Porous Medium with Hall Currents Over an Exponentially Stretching Surface with Non-Linear Thermal Radiation

The impact of trice request slip, non-direct warm radiation, slanted attractive field, Hall flows, compound response and dissemination on non-Darcy convective intensity and mass exchange stream of nanofluid through a permeable medium beyond a dramatically extending sheet with space temperature inclination subordinate intensity sources is well thought-out employ Runge Kutta Shooting strategy the conditions are assessed for various varieties. It is found that an increasing with slip parameter (A1), inclination (a), reduces f ¢,f and enhances g,q. An opposite effect is observed with raising values of second order slip (B), the non-linearity (qw) in thermal radiation leads to a depreciation in the velocity components, temperature and f.

Spectral Relaxation Methodology for Chemical and Bioconvection Processes for Cross Nanofluid Flowing around an Oblique Cylinder with a Slanted Magnetic Field Effect

The current investigation explains the chemical reaction and bioconvection process for an inclined magnetized Cross nanofluid over an inclined cylinder using a spectral relaxation approach. Additionally, the facts concerning swimming gyrotactic microorganisms, non-uniform thermal conductivity, and variable decrease or increase in heat sources are taken together. Each profile is checked for inclined and orthogonal magnetic impact. Appropriate transformations made for conversion of nonlinear PDEs into systems of ODEs. For obtaining numerical results, a spectral relaxation approach is utilized, and graphs are plotted with each physical parameter attached. It is well established that the temperature field intensifies owing to an amplification of thermal conduction and Brownian diffusivity phenomena. The heat transfer rate amplifies owing to a magnification in magnetic parameter and thermal conductivity, but the velocity field diminishes as a result of magnification in the Weissenberg number and power law index. Amplification in the reaction rate constant parameter diminishes the concentration field. Activation energy is the key factor responsible for magnification in the concentration field. Furthermore, smooth agreement is found during comparison with the existing literature. Statistical analysis is also conducted for physical quantities.

Dynamics of radiative Williamson hybrid nanofluid with entropy generation: significance in solar aircraft

Sun based energy is the chief source of heat from the sun, and it utilizes in photovoltaic cells, sun-based power plates, photovoltaic lights and sun-based hybrid nanofluids. Specialists are currently exploring the utilization of nanotechnology and sun-based radiation to further develop flight effectiveness. In this analysis, a hybrid nanofluid is moving over an expandable sheet. Analysts are presently exploring the utilization of nanotechnology and sunlight-based radiation to further develop avionics productivity. To explore the heat transfer rate phenomenon, a hybrid nanofluid stream is moving towards a trough having a parabolic type shape and is located inside of solar airplane wings. The expression used to depict the heat transfer phenomenon was sun based thermal radiation. Heat transfer proficiency of airplane wings is evaluated with the inclusion of distinguished effects like viscous dissipation, slanted magnetic field and solar-based thermal radiations. The Williamson hybrid nanofluid past an expandable sheet was read up for entropy generation. The energy and momentum expressions were solved numerically with the utilization of the Keller box approach. The nano solid particles, which are comprised of copper (Cu) and Graphene oxide, are dispersed utilizing SA (Sodium alginate) as an ordinary liquid (GO). A huge number of control factors, for example, temperature, shear stress, velocity, frictional element along with Nusselt number are investigated in detail. Intensification of thermal conduction, viscous dissipation and radiation improve the performance of airplane wings subjected to heat transmission. Hybrid nanofluid performance is much better than the ordinary nanofluid when it comes to heat transmission analysis.

Analysis of heat transfer transition of thermally driven flow within a square enclosure under effects of inclined magnetic field

This research pertains to the numerical study on natural convection induced by thermally driven flow under influences of slanted magnetic field with a comprehensive parametric analysis. The influences of Rayleigh number (Ra), Hartmann number (Ha), and oblique angles of magnetic field (θ) are considered in details. The results present that the magnetic field direction has significant influences on streamlines and isotherms in a square enclosure, and the average Nusselt number (NuMean) and maximum streamline function (SMax) are decreased with the magnetic field intensity. Based on the curves of normalized Nusselt number Nu∗ with θ, four heat transfer patterns can be observed and called, respectively, Type-1 (single-peak), Type-2 (peak & trough), Type-3 (transition zone), and Type-4 (double-peak). The dimensionless parameter Ha2/Ra is found not to be adequate in determining the heat transfer modes of changing inclined angle. Numerical experiments with a wide range of Ra and Ha are carried out to explore the heat transfer pattern, and a correlated expression for heat transfer transition is proposed to indicate the switching of heat transfer pattern dominated by the inclined magnetic field. By increasing the Ra number, Ha number is examined to interpret the conditions for transition between these four heat transfer patterns.

Thermal capability and entropy optimization for Prandtl-Eyring hybrid nanofluid flow in solar aircraft implementation

In addition to photovoltaic cells, solar power plates, photovoltaic lights, and solar pumping water, solar energy is the primary source of heat from the sun. At the moment, researchers are looking at the use of nanotechnological and solar radiation to increase aeronautical efficiency. In this study, hybrid nanofluid flow linearly passes through a parabolic trough solor collector (PTSC) on the interior of solar aircraft wings to study heat transmission. Solar radiative flow was the term used to describe the heat source. The heat transfer efficiency of the wings is evaluated for several effects, such as a slanted magnetic field, viscous dissipation, play heating, and thermal radiative flow. Entropy generation study was performed on the Prandtl-Eyring hybrid nanofluid (P-EHNF). The Keller box technique was used to solve the predicted energy and momentum equations. As a typical fluid, EG (ethylene glycol) is used to disperse the nanosolid particles, which consist of copper (Cu) and cobalt ferrite (CoFe2O4). A variety of control factors, including velocity, shear stress, and temperature outlines as well as a frictional factor and Nusselt number, are addressed in detail. Thermal radiation amplification and variable thermal conduction parameters appear to increase the efficiency of aircraft wings in terms of thermal transfer. Hybrid nanofluid is superior to conventional nanofluid in terms of heat transmission. Cu-EG has a low thermal efficiency between 3.8% and 4.8% than CoFe2O4-Cu/EG nanofluid.

Magnetohydrodynamics Peristaltic Flow of a Couple-Stress with Varying Temperature and concentrationfor Jeffrey Fluid through a Flexible Porous Medium


 The topic of this paper is the peristaltic motion of a non-Newtonian Jeffrey fluid with couple stress across a porous medium inside a horizontal conduit. The unit is strained by a uniform magnetic field. It is taken into account the effects of viscous dissipation, internal heat generation, and radiation. This approach solves the equations of momentum, temperature, and velocity. The numerical formulas for temperature, axial velocity, and velocity are calculated as functionsof the problem's physical parameters. Numerical calculations, as well as the effects of temperature and the inclined slanted magnetic field and concentration on the velocity equation, were conducted for this formula, and the results were shown on the channel wall. The results of the problem's physical parameters In a series of statistics, the effects of this formula are explained numerically and graphically.

Thermal augmentation in solar aircraft using tangent hyperbolic hybrid nanofluid: A solar energy application

The major source of heat from the sun is solar energy, with enormous use of photovoltaic technology, solar power plates, photovoltaic lights and pumping solar water. This time is about the analysis of solar radiation and how the efficiency of solar aircraft may be improved by using solar radiation and nanotechnology. The study is intended to develop analyses of solar aircraft hybrid nanofluid transfer via parabolic trough surface collector solar wings. Solar radiative flow was named the heat source. The heat transfer efficiency of the wings is evaluated for various phenomena such as a slanted magnetic field, Joule heating, play heat and thermal radiative flow. The entropy production study was carried out in the instance of the tangent hyperbolic fluid. The modelled energy and momentum formulas were controlled with the well-established Keller box numerical technique. This work consists of ethylene glycol standard fluid with two differing types of nanosolid particles copper and silver. Different control factors for velocities, shear stress and temperature are addressed and shown in the figures and tables as well as surface friction and heat transport rate. In terms of thermal transfer, the efficacy of the aviation wings with thermal radiation amplification and changeable thermal conduction parameters is enhanced. Hybrid nanofluid is an ideal source of heat transmission compared to conventional nanofluids. Silver–copper/ethylene glycol thermal efficiency is reduced between 2.6% and 4.4% than copper–ethylene glycol nanofluid.

Magneto-free-convection flow of a rate type fluid over an inclined plate with heat and mass flux

On a porous layered inclined plate, magneto-free-convection flow of a rate type fluid is investigated. The problem is modeled as natural convection for oscillating and general movements of an inclined plate moving in a magnetized medium with a slanted external magnetic field that is either stationary or moving in tandem with the plate. The plate is subjected to a symmetric temperature field with double-sided thermal operation. Constant concentration, first order chemical reaction, and thermal conductivity as a general feature of time are used in heat transfer measurement. On the velocity of the fluid, the impact of varying plate angles with the vertical as well as the slanted angle of the magnetic field with the plate are studied. The motion of the plate and temperature distribution in specific situations was discussed. We can retrieve many results by changing the values of the functions and parameters in our general solutions, including the related results for the viscous fluid from the literature as a limiting case. As a result, the matter of identical models is no longer an issue. Furthermore, graphical software is used to do parametric analysis on fluid dynamics.

Incidences of aligned magnetic field on unsteady MHD flow past a parabolic accelerated inclined plate in a porous medium

AbstractAn exact analysis of a radiative hydromagnetic flow behavior over a tilted parabolic plate through a permeable medium along with variable species concentration and fluid temperature in the presence of a slanted magnetic field parameter, chemical reaction, and heat generation has been carried out in this study. Closed‐form analytical benchmark solutions for flow‐governing equations are obtained by using the Laplace transform method. Thereafter, the incidences of different important physical entities on the nondimensional velocity field, temperature distribution, and species concentration are presented using graphs, whereas impacts of various physical entities on wall shear stress, heat and mass transfer rates are presented in tables. It is worth noting that an increase in the magnetic field and its inclination angle causes the reduction in the fluid velocity. However, wall shear stress increases with the increase of magnetic field and its inclination angle. The novel results in this article can be used to improve quicker cooling and producing miniaturized heat flow systems with upgraded efficiency and cost‐effectiveness.

Heat and Mass Transfer of Natural Convective Flow with Slanted Magnetic Field via Fractional Operators

This article explores the MHD natural convective viscous and incompressible fluid flow along with radiation and chemical reaction. The flow is confined to a moving tilted plate under slanted magnetic field with variable temperature in a porous medium. Non-dimensional parameter along Laplace transformation and inversion algorithm are used to investigate the solution of system of dimensionless governing equations. Fractional differential operators namely, Caputo (C), Caputo-Fabrizio (CF) and Atangana-Baleanu in Caputo sense (ABC) are used to compare graphical behavior of for velocity, temperature and concentration for emerging parameters. On comparison, it is observed that fractional order model is better in explaining the memory effect as compared to classical model. Velocity showing increasing behavior for fractional parameter a whereas there is a decline in temperature, and concentration profiles for a. Fluid velocity goes through a decay due to rise in the values of M, Sc and j. However, velocity shows a reverse profile for augmented inputs of Kp , Gr and S. Tabular comparison is made for velocity and Nusselt number and Sherwood number for fractional models.

A Split Triple-Gate Power LDMOS With Improved Static-State and Switching Performance

A novel split triple-gate (STG) LDMOS is proposed to improve static-state and switching performances. The proposed structure features a triple-gate and split gates (SGs). The triple-gate consists of planar part and trench part, and the SGs are embedded into the drift region and isolated with slanted oxide. The triple-gate enlarges the channel width. Furthermore, the trench part of triple-gate and trench drain–source contributes to a uniform on-state current density distribution from the surface to the bottom of the drift region, resulting in a high average current density. Consequently, the specific ON-resistance ( ${R}_{ \mathrm{\scriptscriptstyle ON},\textsf {sp}}$ ) and the transconductance are improved. In the off-state, the SGs act as a slanted field plate to not only modulate the electric field distribution, but also assist in depleting the drift region to increase the optimal doping concentration, which further decreases the ${R}_{ \mathrm{\scriptscriptstyle ON},\textsf {sp}}$ and maintains a high BV. Moreover, the SG is introduced to reduce the gate–drain capacitance and switching power dissipation. Compared with the triple-gate LDMOS (TG LDMOS), the STG LDMOS not only reduces the ${R}_{ \mathrm{\scriptscriptstyle ON},\textsf {sp}}$ by 66%, but also decreases the gate–drain charge by 41%.

Thermal radiation and inclined magnetic field effects on MHD flow past a linearly accelerated inclined plate in a porous medium with variable temperature

AbstractAn analysis of unsteady MHD natural convective flow, transfer of mass, and radiation past linearly accelerated slanted plate inserted in an immersed permeable medium with uniform permeability, variable temperature, and concentration within the sight of a slanted magnetic field has been done. The novelty of the current examination is to analyze the effect of a slanted magnetic field on the flow phenomena with heat source/sink and destructive reaction for linearly accelerated slanted plate. The governing equations have been solved by using Laplace transform strategy. The estimations of flow velocity, concentration, and temperature are exhibited graphically, while local skin friction, mass, and heat transfer rates are put on view in tabular form for different values of relevant stream parameters. It is fascinating to observe that the raise of inclination angle of an applied magnetic field diminishes both velocity profiles and local skin friction.

Novel Asymmetric Slant Field Plate Technology for High-Speed Low-Dynamic Ron E/D-mode GaN HEMTs

In this letter, we discuss a novel asymmetric field plate structure utilizing a slanted field plate (FP) engineered to appropriately distribute the electric field on GaN high-electron mobility transistors (HEMTs) scaled for low-loss, high-speed power switch applications. A uniform electric field distribution achieved with the slant FP enables an optimum device design, where a low-dynamic ON-resistance ( $\text{R}_{\textsf {on,dyn}}$ ) and high breakdown voltage are obtained simultaneously by minimizing the gate-drain distance. The optimized FP design demonstrated a low $\text{R}_{\textsf {on,dyn}}$ of 2.3 (2.1) $\Omega $ -mm at a quiescent drain voltage of 50V in $\mathsf {E}$ -mode ( $\mathsf {D}$ -mode) HEMTs with a breakdown voltage of 138 V (146 V). The corresponding high-frequency performance of E-mode (D-mode) HEMTs of peak $\text{f}_{\textsf {T}}/\text{f}_{\textsf {max}}= 41$ /100 GHz (53/100 GHz) yielded a decent $\text{R}_{\textsf {on,dyn}} \times \text{Q}_{\textsf {g}}$ product in the range of 31.0–34.5 (28.0–33.3) $\text{m}\Omega \vphantom {^{\int }}$ -nC. This new slant FP technology combined with scaled epitaxial structure (for short $\textsf {L}_{\textsf {g}}$ ) and reduced access resistances, using n+ GaN ohmic contacts, greatly enhances performance and design flexibility of high-speed, low-loss, GaN power switch devices.

Design features and initial operation of a linear plasma device for the feasibility study of charge separation in curved magnetic field

Mitigation of heat flux impinging on divertor plates is a critical engineering issue even for the fusion reactor adopting innovative super-X divertor. In this work, we are exploring the possibility for resolving this problem by converting a substantial portion of thermal energy of ions into electricity in front of the divertor plates. Since successful energy conversion is followed by the separation of electrons from the plasma, the rigorous investigation for the conditions of efficient charge separation is essential. Considering that the charge separation is affected by intricate relations between plasma density, drift velocity, Larmor radius, and field curvature, we have recently designed and constructed a new linear plasma device at Seoul National University for studying the feasibility of the charge separation by curved magnetic field. The device consists of the driving section including a typical electron cyclotron resonance (ECR) plasma source operating at 2.45GHz wave frequency and the diffusion section where a cylindrical chamber is surrounded by a pair of solenoid coils for generating various curved magnetic field structures. The plasma density in the experimental region is measured to be around the middle of 1015m−3 for the optimum ECR field, depending on the gas pressure and microwave power. The preliminary results clearly show that the charged particles in the plasma with a density range of 1015m−3 can be separated quite well by an extremely slanted cusp magnetic field. We are planning to increase the microwave power to increase the plasma density up to 1017m−3, making it possible to investigate charge separation at higher density condition.

Water transport in a PEM fuel cell with slanted channel flow field plates

Cell humidification is an important factor affecting PEM fuel cell performance. A new cell was designed with slanted grooves on both cathode and anode sides to improve water management. Water transport measurements provided information on flooding, hydration, and back-diffusion. The results showed less water flowing out from the cathode side of an anode down-slanted channel than from that of a rectangular channel, because anode down-slanting induced a hydration gradient which caused water back-diffusion into the anode, leading to better performance due to improved membrane hydration and conductivity. At high humidification, performance decreased because of condensation and blocking of the gas diffusion layer, but replacing the rectangular channel with an anode down-slanted channel improved performance to match that of a rectangular cell at normal humidification. However, the cathode down-slanted channel showed membrane dehydration due to water draining away. Moreover, anode or cathode up-slanted channels induced flooding, leading to poor performance.