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RayleighBard convection in a non-Newtonian dielectric fluid with MaxwellCattaneo law under the effect of internal heat generation/consumption
Purpose: The study of instability due to the effects of MaxwellCattaneo law and internal heat source/sink on Casson dielectric fluid horizontal layer is an open question. Therefore, in this paper, the impact of internal heat generation/absorption on RayleighBard convection in a non-Newtonian dielectric fluid with MaxwellCattaneo heat flux is investigated. The horizontal layer of the fluid is cooled from the upper boundary, while an isothermal boundary condition is utilized at the lower boundary. Design/methodology/approach: The Casson fluid model is utilized to characterize the non-Newtonian fluid behavior. The horizontal layer of the fluid is cooled from the upper boundary, while an isothermal boundary condition is utilized at the lower boundary. The governing equations are non-dimensionalized using appropriate dimensionless variables and the subsequent equations are solved for the critical Rayleigh number using the normal mode technique (NMT). Findings: Results are presented for two different cases namely dielectric Newtonian fluid (DNF) and dielectric non-Newtonian Casson fluid (DNCF). The effects of Cattaneo number, Casson fluid parameter, heat source/sink parameter on critical Rayleigh number and wavenumber are analyzed in detail. It is found that the value Rayleigh number for non-Newtonian fluid is higher than that of Newtonian fluid; also the heat source aspect decreases the magnitude of the Rayleigh number. Originality/value: The effect of MaxwellCattaneo heat flux and internal heat source/sink on Rayleigh-Bard convection in Casson dielectric fluid is investigated for the first time. 2020, Emerald Publishing Limited. -
Effectiveness of Hall current and exponential heat source on unsteady heat transport of dusty TiO2-EO nanoliquid with nonlinear radiative heat
The problem of exponential heat source across a flowing nanofluid (TiO2-EO; titanium oxide-Engine oil) containing tiny dust particles on a deformable planar plate has been an open question in meteorology. In this paper, the boundary layer transient two-phase flow of dusty nanoliquid on an isothermal plate which is deforming with time-dependent velocity in the presence of exponential heat source is studied. The impacts of Hall current, nonlinear radiative heat and an irregular heat source (temperature based heat source and exponential space-based heat source) are also accounted. Dusty nanofluid is the composition of dust particles and nanoliquid (TiO2-EO). Using relevant transformations, the system of PDEs is rehabilitated to the system of ODEs and then treated numerically. Exploration of the impacts of pertinent parameters on velocity and temperature fields is performed via graphical illustrations. Numeric data for skin friction factor and the Nusselt number is presented and their characteristics are analyzed/quantified through the slope of linear regression via data points. 2019 Society for Computational Design and Engineering -
Heat transfer enhancement due to nanoparticles, magnetic field, thermal and exponential space-dependent heat source aspects in nanoliquid flow past a stretchable spinning disk
This study explores the heat transfer characteristics of nanoliquid flowing over a rotating disk in the presence of the applied magnetic field and convective boundary condition. The nanoliquid is flowing due to the rotation of the disk with uniform stretching of a disk along the radial direction. Effects of ESHS (exponential space-related heat source) and THS (thermal-related heat source) are the focal concern of this article. The effective thermal conductivity of ethylene glycol (EG)-based graphene oxide (GO) nanoliquid is estimated by using Nans model whereas effective dynamic viscosity is calculated through Brinkman model. The partial differential system which governed the problem is transformed by using Von-Karman stretching transformations to the ordinary differential system. The subsequent two-point ODBVP (ordinary differential boundary value problem) is treated numerically. The consequence of effective parameters of the problem on different flow fields is illustrated graphically. The numerical values of shear stress and heat transfer rate (Nusselt number) are also calculated. Further, the slope of the data points is determined to quantify the outcome. Validation of the present results is made by direct comparison with the available results and an excellent agreement is found. It is found that the rate of heat transfer increased with nanoparticle volume fraction at the rate 0.4153 and the friction factor increased by increasing nanoparticle volume fraction at the rate 3.0681. The fluctuation rate of Nusselt number due to the variation of the ESHS parameter is almost three times more than that of THS parameter. 2020, Akadiai Kiad Budapest, Hungary. -
Significance of Joule heating and viscous heating on heat transport of MoS2Ag hybrid nanofluid past an isothermal wedge
The problem of flow and heat transport of magneto-composite nanofluid over an isothermal wedge has not been addressed in the literature up to yet. Thus, this article features the laminar transport of Newtonian composite nanomaterial (C2H6O2H2O hybrid base liquid + MoS2Ag hybrid nanoparticles) in the presence of exponential space- and temperature-dependent heat source past an isothermal wedge. An incompressible and electrically conducting fluid is assumed. The effects of Joule heating and viscous heating are also accounted. Single-phase nanofluid model and boundary layer approximation are utilized to govern the equations of flow and heat transport phenomena. The solution of the simplified coupled system of dimensionless constraints is obtained by using the RungeKuttaFehlberg method based on the shooting technique. Detailed analysis of active quantities of interest has been presented and discussed. The interesting physical quantities (friction factors and Nusselt number) are estimated. Also, the slope of the data point is calculated in order to estimate the amount of decrease/increase in physical quantities. 2020, Akadiai Kiad Budapest, Hungary. -
Heat transfer optimization of hybrid nanomaterial using modified Buongiorno model: A sensitivity analysis
Sensitivity analysis of the heat transfer rate in the flow of the hybrid nanoliquid C2H6O2?H2O (base liquid) +MoS2?Ag (nanoparticles) over a wedge using the Response Surface Methodology (RSM) is carried out. The nanomaterial is modeled using the modified Buongiorno nanofluid model (MBNM) that considers the major slip mechanisms and the effective properties of the hybrid nanoliquid. Two distinct heat sources- linear thermal heat source and an exponential space-dependent heat source are taken into account. The governing nonlinear two-point boundary-layer flow problem is treated numerically. The effects of pertinent parameters on the flow fields in the boundary layer region are represented graphically with suitable physical interpretations. The exponential heat source and slip mechanisms are used to study the sensitivities of the heat transfer rate. Both heat source mechanisms lead to an improvement in the temperature profile, in which the effect of the exponential space-related heat source is predominant. The Brownian motion parameter was found to be the most sensitive to the heat transfer rate. 2021 -
A study on heat transfer in three-dimensional nonlinear convective boundary layer flow of nanomaterial considering the aggregation of nanoparticles
Thermal systems of solar collectors, electronic cooling, nuclear reactors, and combustion operate at high thermal conditions, and in such circumstances, the density relation of the working fluids with the thermal field may not be linear. The working fluid features are significantly affected by nonlinear density temperature fluctuations. Therefore, a theoretical study of the quadratic Boussinesq approximation (with quadratic density temperature [QDT] variation) and quadratic Rosseland radiation on the three-dimensional boundary layer dynamics and heat transport of ethylene glycol-based titania nanomaterial is carried out. The phenomenon of the kinematics of nanoparticle aggregation is also analyzed by considering modified models proposed by MaxwellBruggeman and KriegerDougherty for thermal conductivity and dynamic viscosity. The flow is induced by the elongation of a flexible flat plate in two directions. A comparison of heat transfer features of linear elongation of the plate and nonlinear elongation of the plate is conducted. The Rosseland radiative heat flux is studied in three different forms. The governing nonlinear equations are treated using apt nondimensionalization, stretching transformation, and then by using the Richardson extrapolation method. The results are presented via plots to analyze the impact of key parameters involved in the model. The magnitude of the nanomaterial temperature is enhanced due to the kinematics of nanoparticle aggregation. Among linear, quadratic, and nonlinear forms of Rosseland radiative heat flux, the quadratic radiative heat is more suitable when QDT is considered. A positive relationship is found between heat transfer and volume fraction and a positive relationship is observed between heat transfer and the QDT factor. The magnitude of the velocities and thermal field is higher for flow driven due to the linear elongation of the plate than the nonlinear case. 2021 Wiley Periodicals LLC -
Entropy generation analysis of radiative heat transfer in Williamson fluid flowing in a microchannel with nonlinear mixed convection and Joule heating
In this article, the spectral quasi-linearization (SQLM) method is implemented to solve the complicated differential equations governing the nonlinear mixed convective heat transfer of a Williamson fluid through a vertical microchannel. Unlike the conventional Boussinesq approximation, the quadratic Boussinesq approximation is taken into account in the formulation. The effects of Rosseland thermal radiation, Joule heating, and viscous dissipation are described in the thermal analysis subjected to the boundary conditions of convective thermal heating. The analysis of entropy production is also performed. The importance of various parameters governing velocity, Bejan number, temperature, and entropy generation was explored using graphic illustrations. It was found that the nonlinear density change with a temperature significantly affects the heat transport in the microchannel and thus increases the magnitude of the Bejan number and the production of entropy. Entropy production occurs maximum due to the boundary conditions of convection heating at the walls of the microchannel. Furthermore, due to a stronger viscous heating mechanism, the magnitude of the Bejan number is reduced, while the production of entropy increases significantly. As a limiting case of the problem, a comparison was made with results previously published in the literature and excellent agreement was established. The calculations provide a solid reference point for future CFD models and are relevant to the dynamics of polymers in microfluidic devices and the polymer industries. IMechE 2022. -
Effects of aggregation on TiO2ethylene glycol nanoliquid over an inclined cylinder with exponential space-based heat source: sensitivity analysis
The current study investigates the impact of nanoparticle (NP) aggregation on nanoliquid flow over an inclined elongating cylinder with an exponential space-related heat source. The dynamic viscosity and thermal conductivity for aggregation structure are modeled by utilizing the Modified Krieger-Dougherty Model and Bruggeman Model correspondingly. The governing equations are solved numerically. Further, the regression model for friction coefficient and heat transport rate is obtained by utilizing the Response Surface Methodology for various space-based heat source parameter (0.5 ? QE? 1.5), mixed convection parameter (1 ? ?? 3) and NPs volume fraction (0.01 ? ?? 0.05). The velocity profile exhibited dual features for different values of curvature parameter and NPs volume fraction. The space-based exponential heat source and mixed convection have an enhancing impact on the skin friction coefficient. It is noticed that the heat transport augments with the addition of nanoparticles. The coefficient of friction is found to be more sensitive to the NPs volume fraction. Further, the heat transport rate is more sensitive toward exponential heat source than NPs volume fraction and mixed convection. 2021, Akadiai Kiad Budapest, Hungary. -
Significance of inclined magnetic field on nano-bioconvection with nonlinear thermal radiation and exponential space based heat source: a sensitivity analysis
The characteristics of heat transport in nanoliquids under the influence of bio-convection (motile microorganism) have significant applications, since nanoliquids have greater capacity to improve heat transport properties than conventional liquids. With these incredible nanoliquid characteristics, the main objective of current research is to examine the impact of the exponential heat source linked to space and the inclined magnetic force on the nano-bioconvective flow between two turntables. The effect of nonlinear thermal radiation, variable thermal conductivity and viscosity aspects are also considered. The complicated nonlinear problem is treated numerically by using Finite difference method. Optimization procedure implemented via Response surface Methodology for the effective parameters thermophoresis parameter, Hartmann number and radiation parameter on the heat transfer rate. The axial velocity is a dwelling function of the inclined angle of the magnetic field, and the variable viscosity parameter. The temperature profile hikes with an exponential space-related heat source and thermal radiation aspects. Also, the heat transport rate is highly sensitive towards nonlinear thermal radiation parameter compared to the thermophoresis effect and Hartmann number. 2021, The Author(s), under exclusive licence to EDP Sciences, SocietItaliana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature. -
Sensitivity analysis of heat transfer in nanoliquid with inclined magnetic field, exponential space-based heat source, convective heating, and slip effects
Sensitivity analysis of the rate of heat transport in the flow of nanoliquids over an elongated sheet using the response surface methodology (RSM) in combination with the face-centered central composite design. The flow is driven due to the velocity slip and the inclined magnetic field effects. Thermal analysis includes aspects of convective heating, Joule heating, viscous heating, and a space-dependent exponential heat source. The nanoliquid model consists of thermophoresis and random motion mechanisms. A set of coupled partial differential governance equations is rehabilitated into a set of ordinary differential equations using the appropriate transformation. Subsequent nonlinear problem is tackled numerically by utilizing finite difference code that employs the formula of four-stage Lobatto IIIa. The rate of heat transport is scrutinized by adopting RSM for three effectual parameters, namely magnetic field parameter ((Formula presented.)), angle of inclination ((Formula presented.)), and suction parameter (Formula presented.)). The velocity and temperature fields were found to be a decreasing function of an angle of inclination of the magnetic field. The velocity range is inversely related to the suction and flow aspects of velocity. Furthermore, the rate of heat transport is more sensitive to the suction parameter than to the magnetic field and to the angle of inclination of the magnetic field. 2020 Wiley Periodicals LLC -
Nanoparticle aggregation effects on radiative heat transport of nanoliquid over a vertical cylinder with sensitivity analysis
A sensitivity analysis is performed to analyze the effects of the nanoparticle (NP) aggregation and thermal radiation on heat transport of the nanoliquids (titania based on ethylene glycol) over a vertical cylinder. The optimization of heat transfer rate and friction factor is performed for NP volume fraction (1% ? ? ? 3%), radiation parameter (1 ? Rt ? 3), and mixed convection parameter (1.5 ? ? ? 2.5) via the face-centered central composite design (CCD) and the response surface methodology (RSM). The modified Krieger and Dougherty model (MKDM) for dynamic viscosity and the Bruggeman model (BM) for thermal conductivity are utilized to simulate nanoliquids with the NP aggregation aspect. The complicated nonlinear problem is treated numerically. It is found that the temperature of nanoliquid is enhanced due to the aggregation of NPs. The friction factor is more sensitive to the volume fraction of NPs than the thermal radiation and the mixed convection parameter. Furthermore, the heat transport rate is more sensitive to the effect of radiative heat compared with the NP volume fraction and mixed convection parameter. 2021, Shanghai University and Springer-Verlag GmbH Germany, part of Springer Nature. -
Significance of nonlinear Boussinesq approximation and non-uniform heat source/sink on nanoliquid flow with convective heat condition: sensitivity analysis
The quadratic convective flow of nanoliquid over an elongating plate subjected to non-uniform heat source/sink, partial slip, and Newton boundary conditions is studied by using the modified Buongiorno model. The correlation for effective thermal conductivity and viscosity of nanoliquid are taken from the experimental work of Corcione. The dimensionless velocity, temperature, rate of heat transport, and mass transport distributions are simulated by solving the nonlinear boundary value problem using the finite difference method. The additional novelty of the present study is an application of response surface methodology to scrutinize the interactive impact of key parameters on the rate of heat transfer. Further, the influence of key parameters is deliberated on various flow fields using the surface and streamline plots. The higher velocities are noticed for the case of nonlinear Boussinesq approximation as compared with the usual Boussinesq approximation. The temperature enhances with a non-uniform heat source/sink aspect. The sensitivity of the heat transfer to the nanoparticle volume fraction remains positive. 2021, The Author(s), under exclusive licence to SocietItaliana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature. -
Radiative heat transfer of nanomaterial on a convectively heated circular tube with activation energy and nanoparticle aggregation kinematic effects
The improvement of the thermal conductivity of the nanoliquid due to the inclusion of a certain amount of nanoparticles is well known. However, the cause of the observed abnormal improvement remains unclear. For this reason, the aggregation kinematics of nanoparticles is significant for evaluating the appropriate thermal effect of particles at the nanoscale. The scope of nanomaterials can be seen in various engineering and industrial fields such as nuclear reactor coolants, heat exchangers, aircraft coolants, microreactor coolants, automobile radiators, solar collectors, etc. Therefore, this study investigates the effects of the aggregation of nanoparticles on radiative nanoliquid flow with activation energy over a horizontal tube subjected to the convective thermal boundary conditions. Experimentally verified correlations of multiwall carbon nanotube aggregation are utilized. The response surface methodology (RSM) is used to determine the optimum levels of the physical parameters to maximize the mass transfer rate of the nanoliquid. The magnitude of the volume fraction and velocity are superior in the absence of aggregation kinematics than in the presence of nanoparticles aggregation mechanism. From the RSM analysis, the maximum Sherwood number obtained is 1.1384 with desirability d = 0.9993. The present results may have applications in nanoliquid-dependent structures, heating/cooling processes, and thermal systems. 2021 Elsevier Ltd -
Radiated flow of chemically reacting nanoliquid with an induced magnetic field across a permeable vertical plate /
Results In Physics, Vol.7, pp.2375-2383, ISSN: 2211-3797. -
Marangoni convective MHD flow of SWCNT and MWCNT nanoliquids due to a disk with solar radiation and irregular heat source /
Physica E : Low-Dimensional Systems And Nanostructures, Vol.94, pp.25-30, ISSN: 1386-9477. -
Nonlinear convective and radiated flow of tangent hyperbolic liquid due to stretched surface with convective condition /
Results In Physics, Vol.7, pp.2404-2410, ISSN: 2211-3797. -
Effects of chemical reaction and partial slip on the three-dimensional flow of a nanofluid impinging on an exponentially stretching surface /
The European Physical Journal Plus, Vol.132, Issue 113, pp.1-18, ISSN: 2190-5444. -
Redefining copreneurs: a four decadal review adopting computer aided text analysis
The study defines copreneurs and presents a four decadal review on copreneurial literature. The purpose is to bring conceptualization and characterization of copreneurs, on surface from its fragmented literature. A structured literature review on copreneurship research published between 1984 and 2023 is conducted. The search is made adopting indexing (Scopus, Clarivate and ABDC), digital libraries including ProQuest and EBSCO, and research articles published in journals by renowned publishers namely Elsevier, Emerald, Inderscience, Sage, Springer, Taylor & Francis and Wiley. Inclusion/exclusion criteria was defined and duplicates were eliminated. Finally, using POWER review model, the existing literature is organized under six themes namely Gender Roles, Spousal Support & Relationship Satisfaction, Work Life Balance, Business Commitment & Motivation, Leadership & Decision Making and Division of Labour & Responsibilities in the Intertwined Worlds. Using Inter- Rater Reliability, five definitions of copreneurs were framed and rated by nine experts from academics and industry. Finally, the definition with highest score and acceptable I-CVI value for simplicity & clarity is proposed. The fragmented literature on copreneurs speaks volume about the need for more impactful research on them. By using the proposed definition of copreneurs, scholars can uniformly identify the copreneurs, with future opportunities for micro-level research on copreneurs. Policy makers can utilise the findings of these research and formulate schemes, policies & programmes for betterment of copreneurs. The study intends to bridge the disciplinary gaps existing for identifying copreneurs and serve as a foundation for information sharing, regarding copreneurs and their entrepreneurial practices. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Theoretical and analytical analysis of convective heat transport of radiated micropolar fluid over a vertical plate under nonlinear Boussinesq approximation
Purpose: In heat transfer problems, if the temperature difference is not sufficiently so small then the linear Boussinesq approximation is not adequate to describe thermal analysis. Also, nonlinear density variation with respect to temperature/concentration has a significant impact on heat and fluid flow characteristics. Because of this reason, the impact of nonlinear density variation in the buoyancy force term cannot be neglected. Therefore in this paper, the unsteady flow and heat transfer of radiating magneto-micropolar fluid by considering nonlinear Boussinesq approximation is investigated analytically. Design/methodology/approach: The flow is fully developed and time-dependent. Heat and mass flux boundary conditions are also accounted in the analysis. The governing equations of transport phenomena are treated analytically using regular perturbation method. To analyze the tendency of the obtained solutions, a parametric study is performed. Findings: It is established that the velocity field is directly proportional to the nonlinear convection parameter and the same trend is observed with the increase of the value of Grashof number. The micro-rotational velocity profile decreases with increase in the nonlinear convection parameter. Further, the temperature profile increases due to the presence of radiative heat aspect. Originality/value: The effectiveness of nonlinear Boussinesq approximation in the flow of micropolar fluid past a vertical plate in the presence of thermal radiation and magnetic dipole is investigated for the first time. 2019, Emerald Publishing Limited. -
LBP-GLZM Based Hybrid Model for Classification of Breast Cancer
Classifying mammogram images is difficult because of their complex backgrounds and the differences in resolutions across the images. One of the toughest parts is telling the difference between harmless (benign) and harmful (malignant) tissue. This is hard because the differences between them are incredibly subtle. As a consequence, the distinctive features embedded within tissue patches become not just relevant but critical for the accurate and automatic classification of these images. Traditionally, efforts to automate this classification process have encountered limitations when relying on a singular feature or a restricted set of characteristics. The subtle variations in texture within these images often render such approaches insufficient in achieving high-quality categorization results. Recognizing this, the present investigation undertakes a more comprehensive approach by incorporating distinct feature extraction techniques - specifically, the utilization of Local Binary Pattern (LBP) and Gray Level Zone Matrix (GLZM). These techniques are adept at capturing and delineating the nuanced texture features inherent in mammogram images. By extracting and analyzing these textural nuances, the aim is to construct a hybrid model capable of classifying mammograms into three distinct categories: malignant, benign, and without the necessity for further examination or follow-up. This proposed hybrid model holds significant promise in the field of mammography classification by leveraging the strengths and complementary attributes of multiple feature extraction methods. The integration of LBP and GLZM aims not only to enhance the accuracy of classification but also to improve the robustness of the system in identifying subtle yet crucial differences in tissue textures. Ultimately, the goal is to create a hybrid feature extraction framework that augments the diagnostic capabilities of mammography, providing more precise and reliable categorization of breast tissue for effective medical decision-making and patient care. 2024 IEEE.