Search

We proposed a linear grooves 3D display that can display 360° viewable 3D images by creating linear grooves that correspond to the viewpoint positions. In the conventional method, arc‐shaped grooves are drawn on a flat substrate of transparent film. However, depending on the viewing position, the image may be distorted. In addition, when a flat substrate is bent into a curved shape, the image is more affected than one observed in a flat shape. Furthermore, the conventional method of arc 3D display method cannot display a 3D image that corresponds to the viewpoint position. In this paper, we propose design and fabrication methods that reduce the image distortion for both flat and curved shapes. A 3D image displayed by the proposed method can change depending on the viewpoint position, and a natural 3D image with motion parallax can be observed. In the experiment, our proposed method fabricated a 360° 3D display by calculating the linear grooves and presented natural 3D images with smooth motion parallax. [ABSTRACT FROM AUTHOR]

The current study aims to investigate heat transfer processes in chemically reacting processes, specifically focussing on the flow of an electrically conducting nanofluid over a curved extended surface. The work tries to describe the complex interaction between heat and mass transport phenomena in many applications, such as the biological sciences, catalytic processes and conflagration by including both homogeneous and heterogeneous processes in the framework. Introducing a convective heating strategy is a new technology that may boost circulation phenomena, perhaps leading to improved heat transfer performance. Additionally, the comparison between the Xue and Tiwari–Das models provides helpful insights into their individual suitability and precision in representing the heat transfer mechanism inside the examined system. The boundary layer approximation is used to handle the mathematical equations. Using the proper similarity variables, the controlling partial differential equations (PDEs) are effectively refined into the dimensionless form and computed numerically utilising the Runge–Kutta Fehlberg 4th–5th-order technique. The suggested characteristics of the physical parameters are examined and their relevant behaviour is illustrated graphically. The outcomes declare that the rise in magnetic parameter will decline velocity while enhance thermal profiles. Homogeneous and heterogeneous reaction strengths will decline the mass distribution while heat source/sink, solid fraction and Biot numbers will improve the temperature profile. In all circumstances, the Xue model exhibits a higher rate of thermal dispersion and temperature profile than the Tiwari–Das model. [ABSTRACT FROM AUTHOR]

The performance of heat transportation fluids in thermal engineering applications enforces us to investigate the combined impacts of magnetisation and radiating heat considering a hybrid nanofluid flow. The transport phenomena of the proposed hybrid nanofluid through a curved surface in a porous medium are analysed by considering ferrite nanoparticles. The surface is preamble and expanding/contracting exponentially. Additionally, it is not wise to neglect the role of Joule dissipation since properties of magnetisation are involved in the proposed phenomena. To analyse the system, a suitable similarity rule is employed to change the governing equation into an ordinary equation. The resulting set of equations is then numerically solved by implementing the “Runge–Kutta” method associated with the “shooting technique”. The quantitative numerical values coincide with prior published work showing validation of the current result vis-à-vis the convergence criteria. However, the findings of the result reveal that the magnetisation and thermal radiation significantly improve the fluid flow and enhance the rate coefficients. Due to the impressive utility of the heat transport phenomenon in manufacturing various electronic devices, cooling of microchips, drug delivery processes, etc. the role of nanoparticles presents its vital role. [ABSTRACT FROM AUTHOR]

The current study investigates the boundary layer flow of Carreau‐Yasuda (C‐Y) ternary hybrid nanofluid model in a porous medium across curved surface stretching at linear rate under the influence of applied radial magnetic field. Al2O3$$ A{l}_2{O}_3 $$, Fe3O4$$ F{e}_3{O}_4 $$ and SiO2$$ Si{O}_2 $$ are nanoparticles and ethylene glycol is considered as base fluid. The effects of viscous dissipation and ohmic heating are present in the energy equation. The governing partial differential equation (PDEs) is nondimensionalized using non‐similarity transformations. They can be treated as ordinary differential equations (ODEs) using local non‐similarity method and solutions are obtained via bvp4c MATLAB tools. The results are evaluated by introducing computational intelligence approach utilizing the AI‐based Levenberg–Marquardt scheme with a backpropagation neural network (LMS‐BPNN) to investigate flow stability. The authors intend to use AI‐based LMS‐BPNN is to optimize the behavior of the hybrid nanofluid (HNF) flow of Carreau‐Yasuda fluid across a stretching curved sheet. Initial/reference solutions are obtained through bvp4c function (an embedded MATLAB function designed to solve systems of ODEs) by systematically adjusting input parameters as demonstrated in Scenarios 1–5. There are three options to divide the numerical data: 80% for training, 10% for testing, and an additional 10% for validation. The LMS‐BPNN is used for approximate solutions of Scenario 1–5. The efficiency and reliability of LMS‐BPNN are validated through fitness curves based on correlation index (R), error, and regression analysis. The velocity and temperature profiles asymptotically satisfy boundary conditions of Scenario 1–5 with LMS‐BPNN. [ABSTRACT FROM AUTHOR]

The generation of dendrites is a common issue of lithium metal battery, while the failure mechanism is still uncovered especially at low current densities/capacities. To better understand the mechanical factors caused by lithium morphologic evolution in the whole dynamic process of a cycle, this study proposes a failure mechanism of the lithium metal anode under a safe condition of rather low current density/capacity. The anode and the electrolyte fail to maintain effective contact throughout the dynamic cycling process due to the accumulation and extrusion of lithium deposits. To guarantee effective contact, a facile and low‐cost mechanical stamping method for lithium metal anode modification is accordingly presented. The curved lithium electrode can stably cycle for more than 300 cycles at 3 mA cm−2. This study is believed to provide a more in‐depth understanding toward the evolvement of lithium morphology to boost practical use of the lithium metal anodes. [ABSTRACT FROM AUTHOR]

Application, Purpose, and Methodology: The Soret and Dufour effects, which are also referred to as cross-diffusion gradients, are advantageous to the manufacturing of binary alloys, the transmission of groundwater contamination, the extraction of oil, and the separation of gas. These are an example of a gradient, which occurs when substances diffuse over one another. The Dufour effect is responsible for the transfer of heat, whereas the Soret effect is concerned with the movement of materials. Both effects are caused by differences in concentration. Temperature differences are the link between the two effects. The Soret and Dufour statistics, in conjunction with the joule heating process, are utilized by us. Through the use of the convergent series, solutions for temperature, speed, and concentration are ultimately found. Core Findings: The findings of these investigations may give researchers engineering and industrial solutions that are unique and advantageous. The computation that is being done right now demonstrates that the sense of radial velocity diminishes as the Hartman number increases. In addition, the temperature of the fluid drops when there is a greater quantity of Prandtl and Soret than before. Methodology: Using the proper transformations, the numerical solution to the micropolar fluid flow problem over a curved stretched disk entails simplifying the partial differential equation system into an ordinary differential equation. This is done to solve the problem. In the process of converting partial differential equations into ordinary differential equations, similarity transformations are utilized. During the shooting process, we use the Runge-Kutta method to solve coupled equations and obtain numerical solutions. By utilizing the nondimensional radius of curvature, we can determine the nondimensional radius of curvature and report the fluid. Future Work: When compared to flat sheets, curved stretched sheets exhibit differences that result in significant boundary layer strain. This is something that will be worked on in the future. Research in the future might concentrate on further investigating these distinctions and the practical ramifications they have, with the possibility of expanding the scope of the investigation to include a variety of engineering and industrial applications in which these effects play an important role. [ABSTRACT FROM AUTHOR]

This paper analyzes the heat transport phenomena of two-phase nanofluid within a permeable circular segment with an interaction of Arrhenius activation energy and, examines the interaction of convective boundary conditions affecting the flow characteristics. The pre-exponential factor of the Arrhenius equation deals with the collision between molecules, and it has significant applications for getting the rate of a chemical reaction and is used to estimate material properties with changes in temperature and energy. To a greater extent, the external uniform heat source encourages thermal properties on account of the behavior of Brownian and thermophoresis parameters. The transformation of the standard nondimensional form of the governing equations is obtained for the assumption of appropriate similarity variables and stream function. The set of these transformed equations is tackled numerically with the shooting technique. The characteristics of physical parameters on the flow phenomena are presented graphically and the validation with earlier research displays a strong correlation for the specific case. The special attraction of the present investigation is the regression analysis for the simulated results of heat and solutal transfer rates using Response Surface Methodology considering various characterizing parameters like heat source, thermal radiation, curvature, activation energy, thermal and solutal Biot numbers within certain range. [ABSTRACT FROM AUTHOR]

Obtaining an efficient heat transfer fluid is currently a significant challenge in various industries, including production processes and biomedical applications such as drug delivery systems. In line with this, the study aims to investigate the velocity slip impact along with convective heat transfer on the flow of tri-hybrid nanofluid over an expanding curved surface. Electrically conducting fluid suspended with nanoparticles enhances thermal properties; however, incorporating an exponential heat source with convective heat transfer properties further energises heat transport phenomena. The proposed model, described by nonlinear differential equations, is transformed into non-dimensional nonlinear ordinary differential equations using suitable similarity rules. These equations are then solved by using a semi-analytical technique, i.e., the Adomian decomposition method with controlled parameters. Moreover, the important outcomes are that the combined effect of all the nanoparticles forms the tri-hybrid nanofluid overrides the fact of nanofluid and hybrid nanofluid in all cases of velocity and temperature distribution. Further, the fluid temperature augments significantly for the enhanced magnetization, but the impact is reversed for the fluid velocity. The two-dimensional flow of tri-hybrid nanofluid in association with the role of velocity slip and convective heat transport properties shows a greater impact for the higher thermal conductivity. The electrically conducting fluid, due to the imposition of the transverse magnetic field along with an exponential heat source, has several industrial as well as engineering applications. The dissipative heat effect, including Joule dissipation, is vital in cancer therapy, drug delivery systems, peristaltic pumping processes, etc. [ABSTRACT FROM AUTHOR]

Inconel718 alloy is widely used in the manufacture of curved parts in aviation and aerospace domain due to its excellent thermal and structural properties. The traditional grinding methods frequently results in low machinability such as grinding burns, surface scratches and clogging in grinding wheel for difficult-to-machine materials. In this work, to eliminate the undesirable outcomes of conventional grinding process, high-shear and low-pressure precision grinding of complex curved Inconel718 workpiece was proposed using specially developed super-elastic composite abrasive tool (ECAT). That was attached to the in-house developed machining system. The influence of composition parameters in various abrasive layers on surface roughness and material removal depth were investigated. The optimal composition parameter of the abrasive layer was determined. The surface morphology, surface profile of the workpiece under different grinding strokes, and grinding force were examined during the high-shear and low-pressure grinding process. The ECAT grinding characteristics were verified at high-shear and low-pressure regime. It was found that the ground surface roughness decreased from initial 306.4 to 50.0 nm after only 8 grinding strokes under the optimal conditions. Also, the surface quality of Inconel718 alloy specimen was significantly enhanced with excellent profile accuracy. It was validated that the high-shear and low-pressure grinding with the developed ECAT was an effective precision machining process for the complex curved parts made of the difficult-to-machine materials. [ABSTRACT FROM AUTHOR]

A curved heat transfer surface is proposed to improve the condensation process. The flow performance and condensation law in the cosine-shaped flow channel, a special curved surface, are numerically and theoretically studied. A theoretical model of surface filmwise condensation on a curved flow channel is established and the mathematical model is validated. The liquid film thickness equation in different zones of the curved surface is deduced and calculated. The results show that the main condensation heat transfer zone is in the middle zone (25 mm < s < 45 mm) and the wave crest zone (0 mm ≤ s ≤ 25 mm), the temperature gradient of the liquid film surface decreases along the liquid flow direction, and the liquid film thickness becomes thinner with the increase of steam velocity. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids are advanced heat transfer fluids that combine the benefits of traditional nanofluids with additional features to enhance their performance. These fluids have the potential to reduce energy consumption, improve heat transfer proficiency, and enhance the performance of thermal systems in diverse applications. Current work analyzes bioconvective Darcy–Forchheimer hybrid nanofluid flow by porous curved stretched surface. The thermal field is modeled accounting the effects of dissipation and thermal radiation. Chemical reaction and Arrhenius kinetics are accounted in the mass concentration field. Influence of the magnetic field is considered. Bioconvection phenomenon is taken into account to control the random motion of solid tiny particles of copper (Cu) and aluminum oxide (Al2O3) in hybrid base fluid water (H2O)–Ethylene glycol (C2H6O2). Cylindrical nanoparticles with shape factor m = 4.9 are considered. Boundary layer norms are utilized to acquire the flow governing dimensional equations. Appropriate transformations are utilized to alter the dimensional system into non-dimensional one. Runge–Kutta–Fehlberg (RKF-45) method in Mathematica is implemented to explore the effective consequences of involved variables on hybrid nanofluid velocity, motile density, thermal, and concentration fields. Surface drag force, mass, density, and heat transfer rates are tabulated and analyzed. The acquired results depict that the velocity field of hybrid fluid decays through porosity variable and Hartmann number. Motile density of microorganisms diminished versus bioconvection Lewis and Peclet numbers. Intensity of heat transfer boosts via Eckert number and thermal radiation parameter. [ABSTRACT FROM AUTHOR]

Ternary hybrid nanofluids (Thnf) are used in several fields, including enhancements of heat transfer, solar power systems, medical devices, electronics cooling, aviation industry, and automotive sector. Furthermore, Thnf provide a versatile solution to boost energy transport for the industrial applications. In the current analysis, an incompressible magnetized Thnf flow with the natural convection through a curved surface using Darcy–Forchheimer medium is addressed. The heat transfer is simulated by using the Cattaneo–Christov (C–C) heat flux model. Aluminum alloys (Ti6Al4V, AA7072 and AA7075) are dispersed in water (H2O) and ethylene glycol (C2H6O2) to synthesize the modified hybrid nanofluid. The model equations are reform into ODEs (ordinary differential equations) by using the similarity substitution. The non-dimensional set of ODEs is further numerically estimated through PCM (Parametric continuation method). The physical behavior of velocity, energy outline, Nusselt number and skin friction for distinct values of emerging variables are computed and analyzed in detail. The finding reveals that an improvement in entropy generation has been observed versus the rising values of unsteadiness and variable porosity parameters. The rising effect of permeability parameter enhances the velocity curve; whereas, fluid velocity drops with the influence of inertia coefficient. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Maxwell fluid flow over a curved surface with the impacts of nonlinear convection and radiation, temperature‐dependent properties, and magnetic field are investigated. The governing equations of the physical system are solved using wavelet based physics informed neural network, a machine learning technique. This is an unsupervised method, and the solutions have been obtained without knowing the numerical solution to the problem. Given the nonlinearity of the coupled equations, the methodology used is flexible to implement, and the activation function used improves the accuracy of the solution. We approximate the unknown functions using different neural network models and determine the solution by training the network. The special case of the obtained results is examined with the available results in the literature for validation of the proposed methodology. It is observed that the proposed approach gives reliable results for the analyzed problem of study. Further, an analysis of the influence of flow parameters (deborah number, variable thermal conductivity and viscosity parameter, velocity slip parameter, temperature ratio parameter, suction parameter, and convection parameters) on temperature and fluid flow velocity is carried out. It is observed that as the flow parameter Deborah number, velocity slip parameter, and viscosity parameter increase, there is a decline in velocity and an enhancement in temperature. This study of fluid flow over a curved surface has applications in the polymer industry, which plays an important role in the manufacturing of contact lenses. [ABSTRACT FROM AUTHOR]

The basic objective of this article is to highlight the impact of Joule heating, thermal radiation, and viscous dissipation on heat transfer rate and friction drag in the flow of viscous nanofluid subject to the curved stretching sheet. Moreover, the effects of magnetic field and two-heating process termed as prescribed surface temperature and prescribed heat flux is considered on the surface. The nanofluid is addressed as a mixture of alumina ( $ Al_2O_3 $ A l 2 O 3 ) nanoparticle and ethylene glycol ( $ C_2H_6O_2 $ C 2 H 6 O 2 ) base fluid. Initially, certain dimensionless variables have been addressed to modify the governing partial differential equation (PDEs) and the associated boundary condition into non-dimensional ordinary differential equations (ODEs) coupled with boundary conditions. Subsequently, the resulting equations are solved numerically by implementing bvp4c package in MATLAB. Multiple graphical results for heat transfer rate, friction drag, velocity, and temperature are obtained under the influence of several flow parameters like radiation parameter, Eckert number, curvature parameter, stretching parameter, Hartmann number, and volume fraction of nanoparticles. Moreover, several interesting results for the flat surface ( $ K \to \infty $ K → ∞), with prescribed heat flux and surface temperature have been determined. The current radiative and dissipative flow coupled with the Joule heating process have countless applications in various industrial and engineering techniques. [ABSTRACT FROM AUTHOR]

In the process of surface forming through line heating of a steel plate, accurately determining the position of the heating lines is crucial to achieving the desired curvature. In this study, we propose a Faster R−CNN based model to predict the positions of heating lines from images of the desired curved surface. Initially, a finite element model for line heating on a steel plate is employed to obtain deformation analysis results based on the positions of the heating lines. The shape resulting from the combination of heating lines is acquired by superimposing the deformation analysis results of each heating line. Color map images of curved surfaces and corresponding information about heating lines are utilized as training data for the proposed model. The model is subjected to training through backpropagation to minimize the total output error. Testing the trained model revealed that the model accurately predicted the positions of the heating lines to achieve the desired surface. Furthermore, validation of the model on a surface with arbitrary curvature confirmed that heating the plate based on the predicted positions of the heating lines resulted in obtaining a curved surface that was very similar to the arbitrary target surface. Consequently, it was determined that the model could be effectively utilized to predict the positions of the heating lines in the line heating process. [ABSTRACT FROM AUTHOR]

The present investigation describes the flow of a copper (Cu) and cobalt ferrite (CoFe2O4) hybrid nanofluid with water as base fluid across a curved surface stretched with nonlinear power-law velocity in the presence of Lorentz forces. The influence of Joule heating and heat source/sink on fluid flow has also been studied. Using a similarity structure, nonlinear partial differential equations are converted into ordinary differential equations which are numerically computed using the ODE analyzer. Skin friction, Sherwood number and Nusselt number are computed in addition to the momentum, mass and energy profiles. A comparison is analyzed through graphs, tables and results for linear and nonlinear surfaces. The heat sink lowers the temperature profile and the heat source elevates the energy field, which serves a purpose in the petrochemical industries for heating and cooling fluids. When the chemical reaction parameter expands, the concentration profile gets less molded, but the opposite tendency is noticed for a decrease in the chemical reaction parameter, which is advantageous for biological applications. The major finding of the study is that nonlinear surfaces exhibit more drag force, mass and heat rate than linear surfaces. Additionally, there was a decent agreement between our results and prior findings for surface drag force under restricted conditions.

The focus of the current study is to analyze the non-similar solutions of natural convection transport of Casson fluid over a curved surface in the presence of a magnetic field, joule heating, and heat source. The flow of Casson fluid in the presence of a magnetic field has applications in bioengineering such as MRI, and artificial neural networks (ANNs) are used to optimize MRI images for better diagnostic results. Non-similar transformations are utilized for the conversion of governing equations into dimensionless partial differential equations (PDEs). The dimensionless system of partial differential equations is treated as a system of ordinary differential equations (ODEs) by utilizing the local nonsimilarity method. The solution of coupled ODEs is obtained through BVP4c. Additionally, velocity profile, temperature profile, and local Nusselt number are studied through the Levenberg-Marquardt method using an artificial neural network. A total of 400 datasets are taken, in which 70 % of this data is used for training and the remaining data is used for validation and testing for each case. The results indicate that velocity is decreasing for both Hartman number and Casson parameter. Fluid temperature is increased for the Grashof number, Casson parameter, and nonlinear radiation parameter. The comparison of artificial neural network (ANN) results with numerically computed results has also shown convergence and good accuracy of the obtained results. The ANN predicted values of skin friction and Nusselt number show stability and convergence with high accuracy.

The heat and mass transfer through the second-grade nanofluid across a curved surface is investigated in the present article with the consequences of chemical reaction, activation energy and Ohmic heating. The Buongiorno model is employed to simulate the thermophoretic and Brownian diffusions effect. The flow phenomena for second-grade fluid (SGF) have been modelled in the form of system of partial differential equations (PDEs) which are converted into a system of ordinary differential equations (ODEs) by substituting the similarity variables. The model equations are converted into a system of ODEs by inserting a suitable variable. The set of dimensionless equations along with boundary conditions are evaluated computationally through the numerical differential equation solver (ND Solve) technique. The entropy optimization, energy curve, Nusselt number, mass transfer, Sherwood number, velocity and skin friction are computed and examined versus distinct physical parameters. The finding reveals that the concentration and velocity profile exhibits enhancement as the curvature parameter increases, whereas an opposite trend has been found in relation to the energy outline. Furthermore, the concentration profile raises as the activation energy increased, while diminishes with the augmentation of chemical reaction.

AbstractImproving thermal conductivity of heat transporting fluids is one of the most effective strategies to address practical challenges relating to optimization of heat energy. This novel study aims at employment of some active as well as passive strategies to investigate their engagement in maximizing energy transportation. The active strategies include addition of nanoparticles of three different metal oxides in the water to enhance its heat conductivity. The presence of gyrotactic microorganisms in ternary nanofluid is assumed to improve solubility. We have also considered nanometric phenomenon of Brownian motion and thermophoresis which were declared most effective in heat and mass transport by Buongiorno. Moreover, effects of magnetic force, thermal radiations, nonlinear heat source, activation energy, and chemical reaction are deliberated to estimate effects of their presence on temperature and rheology of ternary nanofluid flow. Apart from said active strategies to control heat and mass flow rate, curvature of curved surface and porous media has been employed to determine their efficacy as passive controls, particularly on ternary nanofluid flow on curved surface. The modeled equations are solved numerically by MATLAB bvp4c package and solution is validated by comparison of acquired results with those already published in literature. The obtained results are discussed in details by providing physical explanations of rheological and thermal behavior of flow. The study concludes that combination of active and passive control strategies can be effectively utilized to improve overall rheological behavior and thermal performance of ternary nanofluid. This study contributes in better understanding of heat and mass transport in ternary nanofluid dynamics with active and passive control strategies promoting advances in research at intersection of these fields having wide range real-life applications and implications. [ABSTRACT FROM AUTHOR]

The curved surface has emerged as new research platform for understanding and manipulating novel electromagnetic behaviors in complex media. In this paper, we explore the anisotropic polaritons on the spherical surface based on Maxwell's fish-eye metric through stereographic projection. Additionally, this phenomenon can be extended to spindle surface by conformal mapping. Our calculations and simulations demonstrate the elliptic and hyperbolic polaritons, excited by an electric dipole on the sphere, will self-focus or focus on the poles on the sphere affected by anisotropic permittivity. Furthermore, we reveal the optical singularity nature of the curved hyperbolic polaritons from the perspective of transformation optics by obtaining the equivalent optical refractive index profiles and the particle potential energy. Based on natural anisotropic materials and metamaterials, the curved polaritons have potential applications in curved surface focusing and chaos regulation. This work not only bridges the transformation optics and anisotropic polaritons at curved surface, but also provides a new route to surface optical field manipulation. [ABSTRACT FROM AUTHOR]

Although single metal sites on graphitic carbon nitride (g-C3N4) are extensively employed in the catalysis field, the related study is based on the flat g-C3N4 surface model, which is far beyond the reality of the curved structure involved in g-C3N4. Herein, g-C3N4 nanorods with diameters of 9.0 and 7.0 nm are synthesized via the hard template approach to support single-atom Co for the catalytic oxidation of cyclohexane. Comprehensive characterizations, combined with theoretical calculations, find that the curved structure would broaden the space of g-C3N4 interlayers, modulate the electronic structure, and reduce the coordination number of atomic Co. The mechanism study reveals that compared with Co atoms on a flat g-C3N4 surface, the low-coordinated Co atoms anchored on a curved g-C3N4 surface are capable of enhancing the reactant adsorption and facilitating the oxygen dissociation, thereby boosting the catalytic cyclohexane oxidation. The cyclohexane conversion on resultant Co/g-C3N4-9 nm reaches up to 22.4% at the overall selectivity of above 95% under mild reaction conditions, outperforming state-of-the-art nonprecious metal-based catalysts. The present work not only offers a synthesis strategy of the effective single-atom metal catalysts for the cyclohexane oxidation but also sheds light on the origin of the enhanced catalytic performance of curved g-C3N4-based catalysts. [ABSTRACT FROM AUTHOR]

Self-shaping systems offer a promising approach for making complex 3D geometries from the material-driven transformation of 2D sheets. However, current research development of such systems is focused on small-scale applications. This study proposes a self-shaping composite for generation of larger-scale curved surfaces suitable for spatial structures. The composite arises from the novel combination of a perforated plate passive layer and a heat-shrinkable active layer. Experimental investigations are undertaken to assess the influence of perforation parameters of the passive layer over the degree of curvature generated in the self-shaping composite system. A 3D scanner and parametric curvature evaluation tool were used to extract and analyse the fabricated surface curvatures. Three key deformation characteristics were identified: the generated surface is cylindrical with dominant curvature in the x-direction; curvature is approximately uniform across the surface width and length; and curvature is strongly influenced by perforation bridge and strap length parameters. Results of this study support the application of self-shaping curved surfaces for customizable discrete structure parts. [ABSTRACT FROM AUTHOR]

The curved surfaces widely exist in three-dimensional inward-turning inlets and variable sectional isolators, which determine the downstream evolution of the converged flow generated by the crossing shock wave/boundary layer interaction, thereby affecting the start performance and combustion efficiency of the hypersonic vehicles. In this work, the converged flow subjected to the curved surfaces is experimentally studied with the nanoparticle-based planar laser scattering method and particle image velocimetry. Results show that the velocity profiles of the converged flow on the transverse plane can be normalized at different angles. The upstream separation size is found to be decreased by the downstream convex surface due to the reduction of backpressure, especially in large-radius cases, whereas the converged flow gradually becomes smooth ought to the dependence of the acceleration effect on the velocity. The concave surface shows an opposite effect on the converged flow, which further indicates that a downstream convex surface is preferred for hypersonic inlets to weakens the flow non-uniformity to improve the inlet performance. • Converged flow generated by the crossing shock wave/boundary layer interaction on the transverse plane is visualized semi-elliptical. • Velocity profile of the converged flow on the transverse plane can be normalized at different angles and expressed in the logarithmic form. • The convex surface makes the converged flow dissipated under the momentum exchange and the expansion effect. • A downstream convex surface is preferred for inlet design. [ABSTRACT FROM AUTHOR]

The current research relates to numerical analysis of the unsteady MHD mixed convective flow over a curved stretching surface. The Dufour and Soret effects, chemical reaction and joule heating are accounted into the flow together with the thermal and velocity slip effects. The governing partial differential equations of the flow which are in curvilinear coordinates are transformed into ordinary differential equations by using suitable similarity transformations. The numerical results are obtained using the MATLAB built-in solver bvp4c. The stability of the numerical technique has been verified and compared with the available literatures. The resultant boundary layer flow field parameters and the parameters of engineering interest have been presented graphically along with tabular data. The results thus obtained show that the surface drag significantly drops by about 9.4% and 23.4% respectively upon enlargement of the curvature parameter (0.5 ≤ K ≤ 0.7) and velocity slip parameter (0.4 ≤ λ ≤ 0.6) at the stretching surface. The thermal boundary layer thickness and heat transfer rate also tend to be drastically depleted as lesser heat gets transferred from the curve surface to the fluid. Incrementing the unsteadiness parameter (0.5 ≤ δ ≤ 1) significantly improves the heat and mass transfer rates by about 13.5% and 13% respectively. It is also found that the rates of heat and mass transfer can be increased by enhancing the Dufour and Soret effects respectively. [ABSTRACT FROM AUTHOR]

AbstractEntropy optimization is crucial for enhancing fluid dynamics and heat transfer, leading to improved efficiency, energy conservation, and environmental sustainability. Recognizing its significance, we examine the influence of radiation, Joule heating, heat sources, mixed convection, and nonlinear slip on the entropy-optimized flow of a dissipative nanofluid over a curved surface. To seamlessly integrate within the MATLAB bvp4c framework, we convert the set of multi-order ODEs, derived from fundamental PDEs via a similarity transformation approach, into a system of first-order ODEs. Graphs and analytical discussions are used to evaluate the parameters of the problem. The velocity within the boundary layer, along with entropy, experiences reduction due to the enhancement in both first- and second-order slip velocity parameters, as well as curvature parameters. The temperature plot improves with the increase in parameters such as the Soret number and Dufour number, as well as radiation. Conversely, the temperature plot reduces with the rise in suction values. The study indicates that a higher Brinkman number is associated with a lower Bejan number, while the first- and second-order velocity slip parameters have a contrasting effect, leading to an increase in the Bejan number. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Casson fluid flow based on a curved surface has been mathematically modeled using Brownian motion and the Darcy-Forchheimer equation of porosity. Similarity variables are applied to convert flow-anchored partial differential equations into basic ordinary differential equations. The MATLAB solver “bvp4c” is utilized to derive numerical responses for the problem under consideration. During the numerical approach, all parameters have been set to their values based on reviewed literatures and numerical solutions for all flow fields have been obtained against the concerned parameters. Additionally, a variety of graphs are created utilizing numerical extractions to discuss the results. The curvature parameter (K=1.5,2.5,3.5,4.5) results in an improvement in velocity distribution (f'η=1=0.32564,0.360142,0.378247,0.385401). The reason is that for higher values of the curvature parameter, the radius of a curved sheet decreases. Hence, a smaller region of sheet will be in contact, which produces a small amount of resistance towards fluid particles, so that the velocity profiles show an enhancement. Increasing inputs of Forchheimer number imply stronger inertial effects and it introduce an additional resistance to flow that's why fluid velocity decreased. Additionally, for a curved stretched sheet, a higher drag force is required compared to a flat plate because curved sheet has a larger surface area while flat plate has a minimal surface area in contact with the fluid.

In this analysis, Sutterby fluid model over a curved surface is considered. The main mechanisms that contribute to the improvement of the convection characteristics of the nanofluid are categorized as Brownian motion and thermophoresis. The radiation and slip mechanism have been studied at curved stretchable surface. The suction/injection impacts also studied. The partial differential equations are converted into ordinary differential equations through transformations.The numerical solution of the specified mathematical model is obtained using the built-in bvp4c tool in MATLAB. The effects of various parameters related to the system of ordinary differential equations are illustrated in the graphs. The influence of some intended parameters through the physical quantities are presented through tabular form.

This paper proposes an array structure with multidirectional remanent magnetization based on hard-magnetic soft materials, which can be used as a soft switch array on planar and curved surfaces. We firstly investigate the displacement response of a hard-magnetic soft switch which is excited by a magnetic field, and related to the magnitude and direction of the magnetic field. When the remanent magnetization direction of the soft switch is opposite to the horizontal component of the magnetic field, the displacement response is greater than that of the driving magnetic field in other directions. The maximum displacement of the soft switch can reach 4.5 mm under a 6 V driving voltage applied to the Helmholtz coil. We further design 2 × 2 and 3 × 3 switch arrays and the circuit structures of the switch arrays. The switch arrays are fabricated, and the displacement responses of the switch arrays under different driving magnetic fields on planar and curved surfaces are finally demonstrated. When the Z-axis displacement of the device reaches more than 3 mm, the LED light can be switched on. The hard-magnetic soft switch array structure designed in this paper can enable the application of soft switches in curved environments, verifying the feasibility of the application of hardmagnetic soft switch arrays. It is expected to provide a guidance for the design and manufacturing of multi-functional hard-magnetic soft switches in the future and the application of hard-magnetic soft switch arrays in planar and curved environments. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) is of critical significance in the advancement of fuel cells and zinc‐air batteries. The iron‐nitrogen (Fe−Nx) sites exhibited exceptional reactivity towards ORR. However, the task of designing and controlling the local structure of Fe species for high ORR activity and stability remains a challenge. Herein, we have achieved successful immobilization of Fe species onto the highly curved surface of S, N co‐doped carbonaceous nanosprings (denoted as FeNS/Fe3C@CNS). The induction of this twisted configuration within FeNS/Fe3C@CNS arose from the assembly of chiral templates. For electrocatalytic ORR tests, FeNS/Fe3C@CNS exhibits a half‐wave potential (E1/2) of 0.91 V in alkaline medium and a E1/2 of 0.78 V in acidic medium. The Fe single atoms and Fe3C nanoparticles are coexistent and play as active centers within FeNS/Fe3C@CNS. The highly curved surface, coupled with S substitution in the coordination layer, served to reduce the energy barrier for ORR, thereby enhancing the intrinsic catalytic activity of the Fe single‐atom sites. We also assembled a wearable flexible Zn‐air battery using FeNS/Fe3C@CNS as electrocatalysts. This work provides new insights into the construction of highly curved surfaces within carbon materials, offering high electrocatalytic efficacy and remarkable performance for flexible energy conversion devices. [ABSTRACT FROM AUTHOR]

It is very significant and practical to explore a triple hybrid nanofluid flow across the stuck zone of a stretching/shrinking curved surface with impacts from stuck and Lorentz force factors. The combination (Ag–TiO2–Al2O3/blood) hybrid nanofluid is studied herein as it moves across a stagnation zone of a stretching/shrinking surface that curves under the impact of pressure and Lorentz force. Exact unsolvable nonlinear partial differential equations can be transformed into ordinary differential equations that can be solved numerically by similarity transformation. It was discovered that predominant heat transfers and movement characteristics of quaternary hybrid nanofluids are dramatically affected. Numerous data were collected from this study to illustrate how parameters of flow affect the temperature, velocity, heat transmission, and skin friction characteristics. The axial and radial velocities for both fluids (Newtonian and ternary hybrid nanofluid) are increased due to the increasing function of the curvature parameter, magnetic field, and suction parameter. Additionally, the direct relationship between the temperature and heat transfer decreases the heat transfer rate by the curvature parameter, magnetic field, suction parameter, Prandtl number, and heat source/sink. The higher the values of the curvature parameter, the higher the shear stress and velocity.

Abstract The equipment used in various fields contains an increasing number of parts with curved surfaces of increasing size. Five-axis computer numerical control (CNC) milling is the main parts machining method, while dynamics analysis has always been a research hotspot. The cutting conditions determined by the cutter axis, tool path, and workpiece geometry are complex and changeable, which has made dynamics research a major challenge. For this reason, this paper introduces the innovative idea of applying dimension reduction and mapping to the five-axis machining of curved surfaces, and proposes an efficient dynamics analysis model. To simplify the research object, the cutter position points along the tool path were discretized into inclined plane five-axis machining. The cutter dip angle and feed deflection angle were used to define the spatial position relationship in five-axis machining. These were then taken as the new base variables to construct an abstract two-dimensional space and establish the mapping relationship between the cutter position point and space point sets to further simplify the dimensions of the research object. Based on the in-cut cutting edge solved by the space limitation method, the dynamics of the inclined plane five-axis machining unit were studied, and the results were uniformly stored in the abstract space to produce a database. Finally, the prediction of the milling force and vibration state along the tool path became a data extraction process that significantly improved efficiency. Two experiments were also conducted which proved the accuracy and efficiency of the proposed dynamics analysis model. This study has great potential for the online synchronization of intelligent machining of large surfaces.

The conversion of solar radiation to thermal energy has recently much interest as the requirement for renewable heat and power grows. Due to their enhanced ability to promote heat transmission, nanofluids can significantly improve solar-thermal systems' efficiency. This section aims to study the heat transfer behavior of the Sutterby hybrid nanofluid flow of magnetohydrodynamics in the presence of a non-uniform heat source/sink and linear thermal radiation over a non-Darcy curved permeable surface. A novel implementation of an intelligent numerical computing solver based on multi-layer perceptron (MLP) feed-forward back-propagation artificial neural network (ANN) with the Levenberg-Marquard algorithm is provided in the current study. Data were gathered for the ANN model's testing, certification, and training. Established mathematical equations are nonlinear, which are resolved for velocity, the temperature in addition to the skin friction coefficient, and the rate of heat transfer by using the bvp4c with MATLAB solver. The ANN model selects data, constructs and trains a network, then evaluates its efficacy via mean square error. Graphs illustrate the impact of a wide range of physical factors on variables, including pressure, velocity, and temperature. In the entire study, the thermal energy improved by the SiO2 (silicon dioxide) - Au (gold) hybrid nanofluid than the SiO2-TiO2 (titanium dioxide) hybrid nanofluid. The higher internal heat generation/absorption parameter values increase the temperature.

In practical engineering, overlaying on curved surfaces with constantly changing gravity components usually leads to various defects. In this study, Inconel 625 was downward overlaid on curved surface by cold metal transfer (CMT) process with varied heat input, and the dynamic behavior of the molten pool was observed by high speed camera. At high heat input (0.422 kJ/mm and 0.372 kJ/mm), the volume of the molten pool continued to expand due to the downward flow of the liquid, ultimately leading to overflow or instability defects. In contrast, low heat input (0.230 kJ/mm) will make the molten pool shrink during overlaying, which was attributed to the continuously weakened gravity, the relative position between the heat source and the molten pool was then changed. A well-formed and defect-free weld overlay was obtained at optimized heat input 0.230–0.280 kJ/mm. Compared with gas tungsten arc welding (GTAW) process, the weld overlay obtained employing CMT process has the largest thickness and the most uniform fusion line, while the content of Fe element was less than 0.5%. It was confirmed that CMT technology has great potential for overlaying on curved surface.

Recently, flexible transparent conductive films have received widespread attention as important components in the field of organic electronics. Herein, we propose a method for directly constructing flexible transparent conductive films on curved surfaces using silver nanowires as the primary conductive material with the assistance of ethyl cellulose. The uniform transparent conductive film is produced by spray coating the silver nanowires on the curved surface with a curvature diameter of 5 cm. The average sheet resistance is approximately 18.9 Ω sq–1 with a transparency reaching 92.33%, and the standard deviation of the surface resistance is 1.1 Ω sq–1. The inclusion of ethyl cellulose prevents the aggregation of silver nanowires and allows their even distribution on the film surface, which is crucial for achieving a uniform and stable transparent conductive film. Through the analysis and comparison of different types of cellulose, such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, cellulose acetate, and cyanoethyl cellulose, a conclusion has been derived that only cellulose soluble in organic solvents can maintain a homogeneous distribution on the surface of the film without aggregation. Furthermore, changing the magnitude and sign of the curvature did not affect the uniformity of the film. The significant industrial potential of our approach lies in the direct construction of a uniformly transparent silver nanowire network on curved surfaces with applications spanning various fields. Specifically, it can be employed in the realm of electronics, catering to the needs of touchscreens in electronic displays, solar cells, and flexible electronic devices, such as flexible circuit boards. [ABSTRACT FROM AUTHOR]

In this research endeavor, Casson fluid flow and melting heat transfer due to a curved nonlinearly stretching sheet are investigated. The sheet is naturally permeable and the flow is considered in a porous medium. For flow in a porous medium, a modified Darcy's resistance term for Casson fluid is considered in the momentum equation. In the energy equation, heat transport characteristics, including viscous dissipation, are taken into account. Mass transport is also studied together with the impact of chemical reaction of higher order. The governing nonlinear partial differential equations of flow, heat, and mass transport are reduced to nondimensional ordinary differential equations using adequate similarity transformations and then solved numerically employing the bvp4c technique and Runge–Kutta fourth‐order method on MATLAB. The impacts of numerous occurring parameters on relevant fields (velocity field, temperature field, and concentration field) are depicted and discussed by plotting graphs. We concluded the curvature parameter, K $K$ reduces the pace of the flow. The impacts of the stretching index, m $m$ and melting parameter, Me $Me$ are also found to reduce flow and temperature field. Furthermore, we noted that the reaction parameter, Kn ${K}_{n}$ and its order, n $n$ exhibit opposite impacts on the concentration field. Moreover, the numerical values of skin‐friction coefficient and Nusselt number calculated employing bvp4c and Runge–Kutta fourth‐order technique are expressed in tabular mode, and these are found in an excellent match. For validation of the results, skin‐friction coefficient values were computed using the Runge–Kutta fourth‐order technique and bvp4c solver, compared with the existing results, and a good agreement was found. [ABSTRACT FROM AUTHOR]

Curved surface structural parts with hole systems are widely used, and accurate measurement of the hole systems is crucial for assembly and functionality. This study presents a novel approach using machine vision and structural science principles to accurately measure spherical hole systems. We introduce key technologies, including measurement parameter definition, system design, and error modeling, in the paper. Our approach overcomes the limitations of existing methods, offering flexibility, precision, and automation measurement of the hole system. Experimental results demonstrate an accuracy of 0.348′ (arcminutes). This research contributes to the optical measurement of curved surface hole systems and improves their alignment and functionality. [ABSTRACT FROM AUTHOR]

The equipment used in various fields contains an increasing number of parts with curved surfaces of increasing size. Five-axis computer numerical control (CNC) milling is the main parts machining method, while dynamics analysis has always been a research hotspot. The cutting conditions determined by the cutter axis, tool path, and workpiece geometry are complex and changeable, which has made dynamics research a major challenge. For this reason, this paper introduces the innovative idea of applying dimension reduction and mapping to the five-axis machining of curved surfaces, and proposes an efficient dynamics analysis model. To simplify the research object, the cutter position points along the tool path were discretized into inclined plane five-axis machining. The cutter dip angle and feed deflection angle were used to define the spatial position relationship in five-axis machining. These were then taken as the new base variables to construct an abstract two-dimensional space and establish the mapping relationship between the cutter position point and space point sets to further simplify the dimensions of the research object. Based on the in-cut cutting edge solved by the space limitation method, the dynamics of the inclined plane five-axis machining unit were studied, and the results were uniformly stored in the abstract space to produce a database. Finally, the prediction of the milling force and vibration state along the tool path became a data extraction process that significantly improved efficiency. Two experiments were also conducted which proved the accuracy and efficiency of the proposed dynamics analysis model. This study has great potential for the online synchronization of intelligent machining of large surfaces. [ABSTRACT FROM AUTHOR]

During the milling of a curved surface, the shape of the curved surface changes continuously along the milling path, and the direction of the angle between the axis of the milling tool and the normal vector of the machined surface also changes. In turn, these changes greatly affect the quality of the machined surface. Therefore, to improve the surface quality of machined workpieces, the milling tool inclination angle should be optimized. In the present study, a three-dimensional model of the milling tool path and the workpiece surface was created. The three-dimensional surface model of the workpiece at each machining moment was iteratively built based on the Z-map method. From the macroscopic perspective, the influences of different milling tool inclination angles on surface roughness were analyzed. The difference in surface roughness generated by different inclination angles under the same feed rate and pitch was obtained. When cutting with the top of the milling tool, the roughness was larger compared to other inclination angles, and there was a roughness deviation of about 8% when other inclination angles were selected. Moreover, from the microscopic perspective, the material removal rate from a single feed cycle and the optimal inclination angle range for milling stability were explored. An optimal inclination range of 15–30% was obtained, considering both the total material removal volume and unit-angle material removal volume. Finally, a spherical machining verification experiment was conducted on an ultra-precision machining tool, and the experimental findings agreed well with the simulation results, demonstrating the reliability of the proposed model. The theoretical model of this study can provide a basis for optimal cutting tool inclination angle selection during complex surface milling. • A surface model of the workpiece was built based on the Z-map method. • The influences of milling tool inclination angles on surface roughness were analyzed. • The material removal rate from a single feed cycle was explored. • The optimal inclination angle range for milling stability was explored. [ABSTRACT FROM AUTHOR]

The objective of the current study is to develop an investigation on the magnetohydrodynamic flow of viscous liquid through a nonlinear curved enlarging sheet due to the occurrence of heat source. The observation of heterogeneous and homogeneous reactions with the properties of heat source and transverse magnetic field is reflected in this discussion. Further, in a novel approach, the convective heating mechanism enriches the flow phenomena significantly. The governing partial differential equations are successfully transformed into the dimensionless form by using appropriate similarity transformations. The resultant non-dimensional form of equations is computed via the numerical scheme. The properties of the proposed physical constraints are observed and explored their significant behavior graphically. Additionally, the physical properties like surface drag force and local Nusselt numbers are calculated and presented in tabular form. Further, the major outcomes of the study reveal that the fluid velocity retards significantly for higher values of curvature constraint and stretching index and temperature of fluid enhances for the increasing power law stretching index along with the additional Biot number and heat source. [ABSTRACT FROM AUTHOR]

Laser cleaning is an advanced cleaning technology which is widely used in the manufacturing industry. Compared with the common planar laser cleaning process, the laser cleaning process of curved surface is difficult to control the completeness and homogeneity of the cleaning layer, which has a great influence on the surface quality and mechanical properties of the cleaned parts. Therefore, a three-dimensional numerical model of the laser cleaning process of the curved surface considering the coordinate system transformation of the heat source is established in this paper to clean the alumina on the surface of the 5754 aluminum alloy. The temperature distribution characteristics for different tangent slopes of the laser cleaning path and the temperature variation with time for different cleaning paths of the laser cleaning process are analyzed. The results show that the proposed method can provide important guiding significance for the practical laser cleaning process of the curved surface. [ABSTRACT FROM AUTHOR]

The laser‐directed energy deposition technology can be used for additive/subtractive hybrid manufacturing (ASHM). ASHM can realize the manufacturing of some complex parts, such as curved parts. Curved parts will inevitably have some defects during the manufacturing process. However, it is difficult to detect these defects, due to the edge blur of the surface. Therefore, a curved surface quality detection method is proposed. First, the error effect of the curved surface on the surface quality detection is quantitatively analyzed. An efficient channel attention network–DPD network (ECANet–DPDNet) blurry inpainting network model is proposed to effectively reduce the adverse effect of edge blurring. Then, the feature parameters of the repaired image are extracted. The backpropagation (BP) neural network trained by the feature parameters is used to predict curved surface roughness. Finally, two kinds of surface defects are identified using our proposed method based on adaptive threshold segmentation matrix and interference region filtering. The constructed support vector machine (SVM) defect type recognition model is trained using the 15 feature parameters extracted from the defect region. The experimental results show that the accuracy rates for the judgment of scratch defects and pit defects can reach 96.00% and 94.00%, respectively. [ABSTRACT FROM AUTHOR]

The insight of the present work is for analyzing the Darcy-Forchheimer model on energy and mass transfer fluid flow with the impact of CuO and MgO metallic nanoparticles with methanol as base fluid due to an elongated curved surface in uniform porous media numerically. For the two-dimensional physical model, the governing nonlinear coupled partial differential equations are derived with suitable boundary conditions and in turn, using appropriate similarity transformation transferred to nonlinear coupled ordinary differential equations. Runge-Kutta Felhberg (RKF) computational results are carried out using Maple software to understand the characteristics variations of momentum fluid flow, heat and mass transfer on various control non-dimensional parameters of the model viz local Reynolds number, Schmidt number, porosity and curvature parameters. The findings are shown numerically and graphically to demonstrate the performance of flow-related physical parameters on energy, velocity, and concentration patterns. Furthermore, the Nusselt number, skin friction coefficient and Sherwood number for the currently stated system are numerically computed. The Prandtl number denotes the deterioration of the temperature profile's performance. It is believed that increasing the Casson parameter value lowers the velocity field. Moreover, the concentration field declines as the Schmidt number grows. The findings are compared to previous studies which turn out to be in good accord. [ABSTRACT FROM AUTHOR]