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Radiated flow of chemically reacting nanoliquid with an induced magnetic field across a permeable vertical plate
Impact of induced magnetic field over a flat porous plate by utilizing incompressible water-copper nanoliquid is examined analytically. Flow is supposed to be laminar, steady and two-dimensional. The plate is subjected to a regular free stream velocity as well as suction velocity. Flow formulation is developed by considering MaxwellGarnetts (MG) and Brinkman models of nanoliquid. Impacts of thermal radiation, viscous dissipation, temperature dependent heat source/sink and first order chemical reaction are also retained. The subjected non-linear problems are non-dimensionalized and analytic solutions are presented via series expansion method. The graphs are plotted to analyze the influence of pertinent parameters on flow, magnetism, heat and mass transfer fields as well as friction factor, current density, Nusselt and Sherwood numbers. It is found that friction factor at the plate is more for larger magnetic Prandtl number. Also the rate of heat transfer decayed with increasing nanoparticles volume fraction and the strength of magnetism. 2017 The Authors -
Variable viscosity effects on third-grade liquid flow in post-treatment analysis of wire coating in the presence of nanoparticles
Purpose: The features of coated wire product are measured by the flow and heat transport occurring in the interior of dies. Therefore, an understanding of characteristics of polymers momentum, heat mass transfer and wall shear stress is of great interest. Enhancement of heat transfer rate is fundamental need of wire coating process. Therefore, this study aims to investigate the effect of suspended nanoparticles in heat and mass transport phenomena of third-grade liquid in post-treatment of wire coating process. Buongiorno model for nanofluid is adopted. Two cases of temperature dependent viscosity are considered. Design/methodology/approach: The governing equations are modelled with the help of steady-state conservation equations of mass, momentum, energy and nanoparticle concentration. Some appropriate dimensionless variables are introduced. Numerical solutions for the nonlinear problem are developed through RungeKuttaFehlberg technique. The outcome of sundry variables for dimensionless flow, thermal and nanoparticle volume fraction fields are scrutinised through graphical illustrations. Findings: The studys numerical results disclose that the force on the total wire surface and shear stress at the surface in case of Reynolds Model dominate Vogels Model case. Impact of nanoparticles is constructive for force on the total wire surface and shear stress at the surface. The velocity of the coating material can be enhanced by the non-Newtonian property. Practical implications: This study may provide useful information to improve the wire coating technology. Originality/value: Effect of nanoparticles in wire coating analysis by using Brownian motion and thermophoresis slip mechanisms is investigated for the first time. Two different models for variable viscosity are used. 2018, Emerald Publishing Limited. -
MHD flow of SWCNT and MWCNT nanoliquids past a rotating stretchable disk with thermal and exponential space dependent heat source
The main purpose of this investigation is to analyze the impacts of a novel exponential space dependent heat source on MHD slip flow of carbon nanoliquids past a stretchable rotating disk. The flow is created due to rotation and stretching of the disk. Aspects of the convective condition and cross-diffusion (Soret and Dufour effects) are also accounted. A comparative study of nanofluids made up of SWCNTs (single-walled carbon nanotube) and MWCNTs (multi-walled carbon nanotube) is presented. The governing partial differential equations system is reduced to nonlinear ordinary boundary value problem. The RungeKuttaFehlberg is utilized for numerical simulations. Embedded dimensionless parameters on the flow fields are examined via graphical illustrations. The rate of heat mass transfer can be controlled by cross-diffusion, exponential space-based heat source and thermal-based heat source effects. It is also proved that q( ) (? ) x q x SWCNT nanoliquid MWCNT nanoliquid -. A novel idea of the exponential space dependent heat source is implemented in the investigation of the slip flow over a rotating deformable disk under the effects of cross-diffusion, temperature based heat source and magnetic field for the first time. A comparison between two different fluids namely SWCNT-H2O nanoliquid and MWCNT-H2O nanoliquid are studied. 2019 IOP Publishing Ltd Printed in the UK. -
Exploration of non-linear thermal radiation and suspended nanoparticles effects on mixed convection boundary layer flow of nanoliquids on a melting vertical surface
In this paper, the significance of increasing nonlinear thermal radiation on boundary layer flow of some nanofluids is deliberated upon. The effects of magnetic field, melting and viscous dissipation are also considered. The numerical results are obtained for governing flow equations and compared with the previously published results for a special case and found to be in excellent agreement. The effects of various physical parameters such as melting parameter, thermal radiation parameter, temperature ratio parameter and Eckert number on velocity and temperature profiles are analyzed through several plots. The numerical results of physical quantities of engineering interest such as skin friction coefficient and local Nusselt number are presented and discussed in detail. It is found that the nonlinear thermal radiation effect is favourable for heating processes than linear thermal radiation effect. Additionally, the moving parameter and melting parameter can be used to reduce the friction or drag forces. 2018 by American Scientific Publishers All rights reserved. -
Thermal Marangoni convection in two-phase flow of dusty Casson fluid
This paper deals with the thermal Marangoni convection effects in magneto-Casson liquid flow through suspension of dust particles. The transpiration cooling aspect is accounted. The surface tension is assumed to be fluctuating linearly with temperature. The fluid and dust particle's temperature of the interface is chosen as a quadratic function of interface arc length. The governing problem is modelled by conservation laws of mass, momentum and energy for fluid and dust particle phase. Stretching transformation technique is utilized to form ordinary differential equations from the partial differential equations. Later, the numerical solutions based on Runge-Kutta-Fehlberg method are established. The momentum and heat transport distributions are focused on the outcome of distinct governing parameters. The results of Nusselt number is also presented and discussed. It is established that the heat transfer rate is higher in the case of dusty non-Newtonian fluid than dusty Newtonian fluid. The rate of heat transfer can be enhanced by suspending dust particles in a base liquid. 2017 -
Scrutinization of thermal radiation, viscous dissipation and Joule heating effects on Marangoni convective two-phase flow of Casson fluid with fluid-particle suspension
The impact of Marangoni convection on dusty Casson fluid boundary layer flow with Joule heating and viscous dissipation aspects is addressed. The surface tension is assumed to vary linearly with temperature. Physical aspects of magnetohydrodynamics and thermal radiation are also accounted. The governing problem is modelled under boundary layer approximations for fluid phase and dust particle phase and then Runge-Kutta-Fehlberg method based numeric solutions are established. The momentum and heat transport mechanisms are focused on the result of distinct governing parameters. The Nusselt number is also calculated. It is established that the rate of heat transfer can be enhanced by suspending dust particles in the base fluid. The temperature field of fluid phase and temperature of dust phase are quite reverse for thermal dust parameter. The radiative heat, viscous dissipation and Joule heating aspects are constructive for thermal fields of fluid and dust phases. The velocity of dusty Casson fluid dominates the velocity of dusty fluid while this trend is opposite in the case of temperature. Moreover qualitative behaviour of fluid phase and dust phase temperature/velocity are similar. 2018 -
Dual solutions for unsteady stagnation-point flow of prandtl nanofluid past a stretching/shrinking plate
Dual solutions for the time-dependent flow of a Prandtl fluid containing nanoparticles along a stretching/shrinking surface are presented. The nano Prandtl fluid fills the porous stretching/shrinking surface. The Buongiorno model is employed by accounting Brownian motion and thermophoresis slip mechanisms in the analysis. The relevant nonlinear problem is treated numerically via Runge-Kutta-Fehlberg scheme. The flow profiles are scrutinized with respect to the different governing parameters. Results of this study indicate that the temperature boundary layer thickness increased due to the influence of nanoparticles. 2018 Trans Tech Publications, Switzerland. -
Nonlinear thermo-solutal convective flow of Casson fluid over an oscillating plate due to non-coaxial rotation with quadratic density fluctuation: Exact solutions
Purpose: The nonlinear density thermal/solutal fluctuations in the buoyancy force term cannot be ignored when the temperature/concentration difference between the surface and fluid is large. The purpose of this paper is to investigate the nonlinear density fluctuations across a flowing fluid with heat mass transfer effects on a non-axial rotating plate. Therefore, the impact of nonlinear convection in the flow of Casson fluid over an oscillating plate has been analytically investigated. Design/methodology/approach: The governing equations are modeled with the help of conservation equations of velocity, energy and concentration under the transient-state situation. The dimensional governing equations are non-dimensionalized by utilizing non-dimensional variables. Later, the subsequent non-dimensional problem has been solved analytically using Laplace transform method. Findings: The effects of thermal Grashof number, solute Grashof number, nonlinear convection parameters, Casson fluid parameter, unsteady parameter, Prandtl number as well as Schmidt number on hydrodynamic, thermal and solute characteristics have been quantified. The numeric data for skin friction coefficient, Nusselt number and Sherwood number are presented. It is established the nonlinear convection aspect has a significant influence on heat and mass transport characteristics. Originality/value: The effect of nonlinear convection in the dynamics of Casson fluid past an oscillating plate which is rotating non-axially is investigated for the first time. 2019, Emerald Publishing Limited. -
Time-dependent flow due to noncoaxial rotation of an infinite vertical surface subjected to an exponential space-dependent heat source: An exact analysis
The effect of an exponential space-dependent heat source on heat and mass transfer flow of a viscous fluid past an infinite vertical plate is examined. The flow is generated due to noncoaxial rotation of the infinite plate. The noncoaxial rotation creates sine or cosine oscillation in its plane and the fluid at infinity. The flow is assumed to be laminar and time-dependent. The mathematical formulation is developed by considering certain physical initial and boundary conditions. The Laplace transform method is utilized to obtain the exact solutions of the concentration, temperature as well as velocity fields. The Sherwood number, Nusselt number, and skin-friction coefficient are also calculated and presented in tabular form for various embedded parameters. The velocity distributions are obtained for three different cases. The obtained analytical expressions are found to be identical with published results in the limiting sense. 2019 Wiley Periodicals, Inc. -
Quadratic convective transport of dusty Casson and dusty Carreau fluids past a stretched surface with nonlinear thermal radiation, convective condition and non-uniform heat source/sink
Here, the nonlinear convective transport of non-Newtonian fluids embedded with dust particles over a stretched surface is investigated. The silent features of non-Newtonian fluid are considered by Casson and Carreau fluid models. The heat transfer mechanism involves the influences of a magnetic dipole, nonlinear radiative heat and non-uniform heat source/sink. The convective condition is also retained at the boundary. The non-linear partial differential equations that model the transport phenomenon was transformed, non-dimensionalized and parameterized. The subsequent boundary value problems were computed numerically for distinct pertinent parameters using RungeKutta based shooting techniques. The present results are validated with the existing literature by direct comparison. The heat transfer rate in Casson/Carreau fluid phase is significantly higher than that of dust phase. 2019 Elsevier B.V. -
Effectiveness of exponential heat source, nanoparticle shape factor and Hall current on mixed convective flow of nanoliquids subject to rotating frame
Purpose: The study of novel exponential heat source (EHS) phenomena across a flowing fluid with the suspension of nanoparticles over a rotating plate in the presence of Hall current and chemical reaction has been an open question. Therefore, the purpose of this paper is to investigate the impact of EHS in the transport of nanofluid under the influence of strong magnetic dipole (Hall effect), chemical reaction and temperature-dependent heat source (THS) effects. The Khanafer-Vafai-Lightstone model is used for nanofluid and the thermophysical properties of nanofluid are calculated from mixture theory and phenomenological laws. The simulation of the flow is also carried out using the appropriate values of the empirical shape factor for five different particle shapes (i.e. sphere, hexahedron, tetrahedron, column and lamina). Design/methodology/approach: Using Laplace transform technique, exact solutions are presented for the governing nonlinear equations. Graphical illustrations are pointed out to represent the impact of involved parameters in a comprehensive way. The numeric data of the density, thermal conductivity, dynamic viscosity, specific heat, Prandtl number and Nusselt number for 20 different nanofluids are presented. Findings: It is established that the nanofluid enhances the heat transfer rate of the working fluids; the nanoparticles also cause an increase of viscous. The impact of EHS advances the heat transfer characteristics significantly than usual thermal-based heat source (THS). Originality/value: The effectiveness of EHS phenomena in the dynamics of nanofluid over a rotating plate with Hall current, chemical reaction and THS effects is first time investigated. 2019, Emerald Publishing Limited. -
Computational modeling of heat transfer in magneto-non-Newtonian material in a circular tube with viscous and Joule heating
Numerous industrial and engineering systems, like, heat exchangers, chemical action reactors, geothermic systems, geological setups, and many others, involve convective heat transfer through a porous medium. The diffusion rate, drag force, and mechanical phenomenon are dealt with in the DarcyForchheimer model, and hence this model is vital to study the fluid flow and heat transport analysis. Therefore, numerical simulation of the DarcyForchheimer dynamics of a Casson material in a circular tube subjected to the energy losses due to the viscous heating and Joule dissipation mechanisms is performed. The novelty of the present investigation is to scrutinize the convective heat transport characteristics in a circular tube saturated with DarcyForchheimer porous matrix by utilizing the non-Newtonian Casson fluid. The flow occurs due to the elongation of the surface of a tube with a uniform heat-based source/sink. The similarity solution of the nonlinear problem was obtained using dimensionless similarity variables. The effects of operating parameters related to the flow phenomena are analyzed. Further, the friction factor and Nusselt number are also analyzed in detail. The present flow model ensures no flow reversal and acts as a coolant of the heated cylindrical surface; the existence of the magnetic field, as well as an inertial coefficient,acts as the momentum-breaking forces, whereas Casson fluidity buildsit. The Joule heating phenomenon enhances the magnitude of temperature. The thermal field of the Casson fluid is higher at the surface of the circular pipe due to convective thermal conditions. 2021 Wiley Periodicals LLC. -
Magnetohydrodynamic flow of Carreau liquid over a stretchable sheet with a variable thickness: The biomedical applications
Purpose: The magnetohydrodynamic (MHD) flow problems are important in the field of biomedical applications such as magnetic resonance imaging, inductive heat treatment of tumours, MHD-derived biomedical sensors, micropumps for drug delivery, MHD micromixers, magnetorelaxometry and actuators. Therefore, there is the impact of the magnetic field on the transport of non-Newtonian Carreau fluid in the presence of binary chemical reaction and activation energy over an extendable surface having a variable thickness. The significance of irregular heat source/sink and cross-diffusion effects is also explored. Design/methodology/approach: The leading governing equations are constructed by retaining the effects of binary chemical reaction and activation energy. Suitable similarity transformations are used to transform the governing partial differential equations into ordinary differential equations. Subsequent nonlinear two-point boundary value problem is treated numerically by using the shooting method based on RungeKuttaFehlberg. Graphical results are presented to analyze the behaviour of effective parameters involved in the problem. The numerical values of the mass transfer rate (Sherwood number) and heat transfer rate (Nusselt number) are also calculated. Furthermore, the slope of the linear regression line through the data points is determined in order to quantify the outcome. Findings: It is established that the external magnetic field restricts the flow strongly and serves as a potential control mechanism. It can be concluded that an applied magnetic field will play a major role in applications like micropumps, actuators and biomedical sensors. The heat transfer rate is enhanced due to Arrhenius activation energy mechanism. The boundary layer thickness is suppressed by strengthening the thickness of the sheet, resulting in higher values of Nusselt and Sherwood numbers. Originality/value: The effects of magnetic field, binary chemical reaction and activation energy on heat and mass transfer of non-Newtonian Carreau liquid over an extendable surface with variable thickness are investigated for the first time. 2020, Emerald Publishing Limited. -
Flow and heat transport of nanomaterial with quadratic radiative heat flux and aggregation kinematics of nanoparticles
A numerical study of flow and heat transport of nanoliquid with aggregation kinematics of nanoparticles is carried out using the modified Buongiorno model (MBM). The MBM model is composed of random motion nanoparticles, heat diffusion of nanoparticles, and effective properties of nanoliquids. The effects of quadratic variation of density-temperature (quadratic convection), and the quadratic Rosseland thermal radiation are also studied. Inclined magnetism is also taken into account. The aggregation kinematics of nanoparticles is simulated using the modified Krieger-Dougherty model for dynamic viscosity and the modified Maxwell model for thermal conductivity. The main system of nonlinear partial differential equations is solved using the similarity technique and the finite difference method-based algorithm (FDM). The consequence of several key parameters on velocity, nanoparticle volume fraction, wall heat flux, and temperature are found in two cases, namely weak convective heating and strong convective heating. The study reveals that the suspension of the nanoparticles increases the thermal conductivity and, thus, improves the temperature and reduces the heat flux at the plate. The structures of the thermal and velocity surface layer are higher in the case of strong convective heating, while in the case of weak convective heating, the nanoparticle volume fraction layer is thicker. 2021 Elsevier Ltd -
Selection of cobot for human-robot collaboration for robotic assembly task with Best Worst MCDM techniques
Since the first industrial robot was produced at the beginning of the 1960s, robotic technology has completely changed the sector. Industrial robots are made for various tasks, including welding, painting, assembling, disassembling, picking and placing printed circuit boards, palletizing, packing and labeling, and product testing. Finding flexible solutions that allow production lines to be swiftly re-planned, adjusted, and structured for new or significantly modified product development remains a significant unresolved problem. Today's Industrial robots are still mostly pre-programmed to do certain jobs; they cannot recognize mistakes in their work or communicate well with both a complicated environment and a human worker. Full robot autonomy, including organic interaction, learning from and with humans, and safe and adaptable performance for difficult tasks in unstructured contexts, will remain a pipe dream for the foreseeable future. Humans and robots will work together in collaborative settings such as homes, offices, and factory setups to execute various object manipulation activities. So, it is necessary to study the collaborative robots (cobots) that will play a key role in human-robot collaborations. Multiple competing variables must be considered in a thorough selection process to assess how well industrial cobots will work on an industrial working floor. To select a collaborative robot for the human-robot collaborative application, a straightforward multi-criteria decision-making (MCDM) methodology is based on the best-worst method (BWM). The ranking derived using the BWM method is displayed. The outcomes demonstrated the value of MCDM techniques for cobot selection. 2023 IEEE. -
Enhanced Social Media Profile Authenticity Detection Using Machine Learning Models and Artificial Neural Networks
Fake engagement is one of the main issues with online networks or ONSs, which are used to artificially boost an account's popularity, this study examines the effectiveness of seven sophisticated Machine Learning Algorithms, Random Forest Classifier, Decision Tree Classifier, XGBoost, LightGBM, Extra Trees Classifier, and SVM, and got 93% accuracy in Decision Tree Classifier. In order to solve overfitting issues and improve model resilience, the paper proposes Generative Adversarial Networks (GANs) and uses K-Fold Cross-Validation. Furthermore, design a Gan-ANN model that combines Batch Normalization and Artificial Neural Networks (ANN) with GAN-generated synthetic data is investigated. The enhanced dataset seeks to strengthen model performance and generalization when combined with cutting-edge modeling methods. This study aims to improve model scalability, predictive accuracy, and dependability across different machine learning paradigms. 2023 IEEE. -
Sonochemical assisted impregnation of Bi2WO6 on TiO2 nanorod to form Z-scheme heterojunction for enhanced photocatalytic H2 production
In this work, Bi2WO6/TiO2 nanorod heterojunction was prepared by sonochemical assisted impregnation method. After loading 2 wt% Bi2WO6 on TiO2 nanorods, the photocatalytic hydrogen production rate of 2026 mol/h/g was achieved. Compared to commercial P25 and TiO2 nanorods, ?13 and ?3 folds enhanced activity was observed. The excellent photocatalytic performance of Bi2WO6/TiO2 nanorod photocatalyst was mainly attributed to i) reduction of bandgap due to heterojunction formation, ii) quick transport of photogenerated charge carriers, and iii) efficient charge carrier separation supported by UV-DRS, photocurrent measurement, Impedance study, and photoluminescence spectra analysis. The Z-scheme band alignment for Bi2WO6/TiO2 nanorod heterojunction was proposed based on the Mott-Schottky measurement. This result demonstrated the effective utilization of Z-scheme heterojunction of Bi2WO6/TiO2 for photocatalytic reduction application. 2021 The Society of Powder Technology Japan -
A reliable inter-domain routing framework for autonomous systems using hybrid Blockchain
Inter-domain networks face several routing challenges, such as security, scalability, and reliability concerns in existing BGP-based systems. These challenges are exacerbated by the increasing number of interconnected networks and the lack of a standardized approach for routing data between them. Hybrid Blockchain-based framework has proposed for inter-domain routing in autonomous systems in this research. The framework combines the use of traditional routing protocols with the distributed ledger technology of Blockchain. It leverages the salient features of both to create a more secure and efficient routing framework. The Blockchain component provides a decentralized and tamper-proof ledger for storing routing information, while the traditional routing protocols handle the actual exchange of data between autonomous systems. The framework is designed to enhance the security of inter-domain routing by incorporating the use of digital signatures and information sharing among participating autonomous systems. Each participating system maintains a copy of the distributed ledger and can verify the authenticity of routing information using digital signatures. It ensures that only legitimate and authorized data is transmitted between autonomous systems, mitigating the risk of malicious attacks or illegitimate routing. The proposed framework obtained 87.73 % Route calculation Speed, 90.41 % Route filtering, 93.77 % Fault tolerance, 94.10 % Load balancing, 95.54 % Hop count, 95.13 % bandwidth consumption, 93.94 % Security Management and 96.29 % Convergence time. The framework employs a consensus mechanism for updating and validating the routing information, ensuring consistency and accuracy in the routing decisions. It also reduces the reliance on a single central authority and distributes the decision-making process among participating systems. 2024 Elsevier Ltd -
Does environmental policy stringency improve nature's health in BRICS economies? Implications for sustainable development
In our groundbreaking exploration, we meticulously delve into the relationship between environmental policy stringency, international trade dynamics, and financial openness within the BRICS group (Brazil, Russia, India, China, and South Africa) spanning from 1996 to 2021. With a focus on critical variables such as economic growth and technological innovation, our empirical findings challenge conventional wisdom. Surprisingly, we found that those stringent environmental policies, when standing alone, do not invariably lead to reduce CO2 emissions. Equally interesting is our startling discovery that the anticipated moderating influence of environmental policy stringency, catalyzed by trade and foreign direct investment, on the well-being of our environment does not materialize; contrarily, both trade and foreign direct investment moderating channels exhibit unanticipated positive correlations with CO2 emissions. These revelations provoke us with the presence of a "pollution haven" phenomenon within the BRICS economies. Furthermore, our investigation reveals that, when examined individually, trade and foreign direct investment also appear to contribute to elevated emission levels. These findings provide a resolute solution to our research quandary, underlining the indispensable requirement for cutting-edge and robust environmental policies. These policies must possess the prowess to effectively counteract the adverse environmental consequences stemming from the amalgamation of global trade and financial integration. In doing so, they shall propel BRICS nations toward a future firmly grounded in principles of sustainability and ecological integrity. 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Cloud Intrusion Detection Using Hybrid Convolutional Neural Networks
Instead of storing data on a hard drive, cloud computing is seen as the best option. The Internet is used to deliver three different kinds of computing services to users all over the world. One advantage that cloud computing provides to its customers is greater access to resources and higher performance while at the same time increasing the risk of an attack. Intrusion detection systems that can handle a large volume of data packets, analyse them, and generate reports based on knowledge and behaviour analysis were developed as part of this research. As an added layer of protection, the Convolution Neural Network Algorithm is used to encrypt data during end-to-end transmission and to store it in the cloud. Intrusion detection increases the safety of data in the cloud. In this paper demonstrates the data is encrypted and decrypted using a model of an algorithm and explains how it is protected from attackers. It's important to take into account the amount of time and memory required to encrypt and decrypt large text files when evaluating the proposed system's performance. The security of the cloud has also been examined and compared to other existing encoding methods. 2024, Iquz Galaxy Publisher. All rights reserved.