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This study examines how a chemical reaction and a nonuniform heat source effect the flow of an MHD Casson nanofluid over a nonlinear stretching sheet. By incorporating viscous dissipation, the energy equation is strengthened. Brownian diffusion, thermophoresis diffusion effects are taken place. By using the necessary similarity transformations, the governing equations for the current flow are converted into a nonlinear system. The RKF technique yields a numerical solution along with a shooting technique for the condensed system. Thereafter, to better understand the physical interpretation of flow and heat transfer, the flow-controlling parameters are shown graphically and in tabular form in the current work. Based on the present study's numerical results, a fair connection is found between this analysis and previous studies. Some of the observations are velocity profile is decreased for the effects of magnetics and stretching parameter variations and Eckert number plays a great role in the increase of temperature profile. [ABSTRACT FROM AUTHOR]

AbstractThe utilization of molten salts in heat transfer applications, specifically within shell-and-tube heat exchangers, has garnered significant attention for its potential in sustainable energy solutions. this study employs advanced machine learning algorithms, including decision tree regressor, support vector regressor, extreme gradient boosting, and random forest, to not only predict the heat transfer behavior of molten salts but also unravel the complex mechanisms underlying this process. Achieving a remarkable accuracy score of 0.985, the Support Vector Regressor leads the predictive models, closely followed by random forest (0.982), Decision Tree Regressor (0.974), and Extreme Gradient Boosting (0.965). The incorporation of Shapley Additive exPlanations values accentuates the Reynolds number’s pivotal role, elucidating a robust correlation with the Nusselt value. These insights transcend mere prediction, offering a profound understanding that can significantly impact the design and optimization of molten salt heat exchangers. The applications of molten salts extend across various sectors, including concentrated solar energy and thermal storage, solidifying their position as a versatile and effective solution in the pursuit of sustainable and efficient energy systems. [ABSTRACT FROM AUTHOR]

AbstractThis study underscores the critical role of heat transfer modeling in the design and optimization of heat exchangers, recognizing the challenges posed by traditional numerical methods. To address the need for more efficient alternatives, machine learning emerges as a promising solution, leveraging its capacity to unravel intricate relationships in heat transfer processes. The research focuses on forced convection heat transfer involving nanoparticles (specifically TiO2, Al2O3, and Cu) dispersed in water, employing the Lagrangian–Eulerian approach under turbulent flow conditions with a constant surface heat flux. Machine-learning techniques, namely extreme gradient boosting, support vector regression, and tree regression are employed to predict heat transfer outcomes based on collected data. The achieved results exhibit promising accuracy levels, with eXtreme gradient boosting, support vector regression, and tree regression algorithm models demonstrating impressive accuracies of 91%, 91%, and 94%, respectively. The mean absolute errors for these machine-learning models were recorded as 1.07, 7.24, and 3.74. This research serves as a demonstration of the potential of machine-learning methodologies in modeling complex physical systems, as evidenced by their efficiency in capturing the behavior of nanofluids under various conditions. The obtained accuracy and low mean absolute error values indicate the robustness of these machine-learning models in predicting heat transfer results. The implications of these findings are substantial for the field of heat exchanger design and optimization. The study suggests that machine-learning techniques offer a more efficient and cost-effective approach compared to traditional numerical simulations. By leveraging the capabilities of these models, there is potential for enhanced accuracy and efficiency in the design and optimization processes of heat exchangers, contributing to advancements in thermal engineering. [ABSTRACT FROM AUTHOR]

AbstractThis study presents a new model for effective thermal management of a channel with elastic sinusoidal obstacles and pulsating multiple nano-jet impingements. The channel was cooled by alumina Al2O3 in various forms (platelets, blades, cylinders, and bricks) and water as a basic fluid. A hybrid nanofluid (multi-wall carbon nanotube-Fe3O4) was also used. The governing equations were solved using the finite volume method. Results were recorded for Reynolds numbers (Re = 350), Strouhal numbers (St = 0.01–1), pulse amplitude (A = 0.25–1), and the number of slots (Nj = 1–13). The results showed that the cooling efficiency was improved by using pulsating flow by 24.383%. It was also noted that using sinusoidal elastic obstacles improved the heat transfer rate by 8.344%. In addition, the number of slots affected the heat transfer rate, increasing it to 259.983%. The results obtained from this study demonstrate the effectiveness of the proposed design, which incorporates elastic sinusoidal obstacles and pulsating multiple nano-jet impingements, in significantly improving thermal management performance and reliability. These advancements hold great importance in various industrial and consumer applications. [ABSTRACT FROM AUTHOR]

The thermal radiation and convective condition principles were working on specific functions like gas turbines, electrical fuel, renewable energy, projectiles, nuclear power plants, aerospace engineering, and thermal transportation. Considering the aforementioned functions, the present analysis inspected the stagnation point hybrid nanofluids movement over the rotating sphere on the behavior of viscous dissipation and thermal radiation. Silver and Ferrous nanoparticles including the host fluid water were held into affected the flow. The presence of convective boundary conditions is incorporated within the system. Applying appropriate correspondence factors, nonlinear governing equations were transformed with ordinary differential equations. This finite element method is applied to find the mathematical solutions to the boundary conditions and simplified equations. These outcomes convey to temperature was decreased about accelerated factor, although primary velocity was found into increased. The heat transfer was magnified by thermal Biot number, and that rate of development was greater about hybrid nanosuspension. The heat transport method was reduced by the Eckert number; also that reduction rate was similarly dull on hybrid. [ABSTRACT FROM AUTHOR]

A numerical investigation on the impacts of heater length increased from left corner along with the bottom wall in a Cu-water nanofluid-filled porous cavity in the existence of MHD and thermal radiation is performed out. The bottom wall is heated with two different types of heater (both uniform and nonuniform) separately. Three various lengths of heater are considered. Constant cold upper horizontal wall moves in the positive direction. The other sidewalls and excluding the heating portion of the bottom wall are considered to be adiabatic. The system of dimensionless form of governing equations is solved by finite volume method (FVM) with appropriate boundary and initial conditions and SIMPLE algorithm has been employed for the pressure term. For both types of heating, the highest heat transfer is attained with the length of heater L H = 1 / 4 for all taken Richardson number. The effect of magnetic field is very low on heat transfer with the thermal source length L H = 1 / 2 and nonuniform heating in free convection regime. On increasing the heater length in nonuniform heating, overall heat transfer rate is decreased first and then raised. The percentage of increasing of average Nusselt number with an increase of thermal radiation parameter in nonuniform heating is higher than uniform heating. The effect of magnetic field is significant for all taken solid volume fraction in uniform heating than the nonuniform heating with heater length L H = 1 / 2. [ABSTRACT FROM AUTHOR]

Abstract The interfacial nanolayer is a tinny coating of liquid molecules convened around the immersed solid nanoparticles in the base liquid which plays a vital role to control the flow and improve the thermophysical properties of the fluid. Features are more prominent for hybrid nanomaterials. Hence, the present analysis deals with the concomitant effects of an interfacial nanolayer of nanomaterials MWCNT and Ag during a viscous Darcy Forchheimer flow over a moving needle. Thermal radiation, Joule heating, and viscous dissipations concerning the Cattaneo-Christov thermosolutal flux have been introduced. An appropriate transition is applied to rationalize the substantially paired and nonlinear governing equations. Equations after similarity transformation are processed by the finite element method. The impression of different governing parameters on the governing systems in conjunction with entropy and Bejan number is displayed through graphs and tables. Graphs are drawn with an evaluation of general and hybrid nanofluids and different nanolayer thicknesses of nanoparticles. A similarity feature concerns existing literature with good promise. The thermal impact is more significant with the occurrence of Cattaneo-Christov heat flux and is further supported by thermal radiation and the Brinkman number. It has been found that Brinkman numbers boost the rate of heat transfer. Entropy generation is nonlinearly raised with advanced outcomes of radiation parameters, Brinkman number, and Reynolds number, while Bejan number shows the opposite behavior with respect to those parameters. The nanolayer thickness of the nanoparticles restricted the irreversibility phenomena of the system, and the same feature is supported by the Bejan number. [ABSTRACT FROM AUTHOR]

AbstractThis study explores the application of Al2O3-ZnO-Fe3O4/Water ternary nanofluids for enhanced thermal management in engineering applications, addressing the MHD Darcy–Forchheimer problem with an emphasis on optimizing cooling processes in a 2D-wavy cavity under various moving boundary conditions. Aimed at surpassing the limitations of conventional cooling fluids, the research employs the finite volume method within the OpenFOAM® framework to investigate the impact of nanofluid integration on heat transfer efficiency and entropy generation, utilizing partial heating and eight distinct boundary scenarios. By comparing the performance of ternary nanofluids against that of hybrid and mono nanofluids, we identify optimal conditions that significantly enhance cooling effectiveness, as evidenced by a 37% improvement in heat exchange efficiency over water. The findings demonstrate the superior performance of Al2O3-ZnO-Fe3O4/Water nanofluids in achieving higher average Nusselt numbers at low Darcy numbers, despite an increase in entropy. Optimal conditions were identified for the most favorable scenario involving the movement of cavity lids, based on the Nusselt number, specifically in Case 7 (ul1+ and ul2−). Decreasing the number of waves in the cavity enhances heat transfer and reduces irreversibility. Finally, the study shows that the influence of lid motion on skin friction significantly varies with Richardson numbers, and the use of nanofluids over pure water notably reduces skin friction. [ABSTRACT FROM AUTHOR]

AbstractThis article delves into the theoretical analysis of hydromagnetic bioconvection involving a radiating and reacting Casson nanofluid containing motile microorganisms, past an exponentially stretching permeable vertical surface within a porous medium, incorporating heat and mass transfer characteristics. The model problem’s nonlinear differential equations are derived by applying relevant conservation laws and subsequently solved numerically using the homotopy analysis method (HAM). The graphical representation and quantitative discussion of the effects of emerging parameters on various aspects, including nanofluid velocity, temperature distribution, nanoparticles, gyrotactic microorganisms concentration, skin friction, Nusselt number, Sherwood number,and Motile density number are presented. The findings reveal significant influences on both heat and mass transference rates, as well as motile microorganism rates, in response to variations in bioconvection parameters. Additionally, the integration of gyrotactic microbes into nanoparticles is identified as a crucial factor for enhancing the thermal performance of devices, such as microbial fuel cells, bacteria-activated micromixers, microfluidic tools, enzyme biosensors, and chip-like bio microsystems. The bioengineering implications of these results are noteworthy, providing valuable insights for the design and optimization of relevant technologies. [ABSTRACT FROM AUTHOR]

AbstractThis research focuses on investigating the impact of magnetized nanoparticles’ heat and mass transfer process two-dimensional (2D) porous medium ternary hybrid Magnetohydrodynamics (MHD) ferrofluid flow through a two movable permeable porous surface, with a specific emphasis on the Darcy Forchheimer effect, activation energy, and chemical reaction parameters. Recently, motile microorganisms have become a significant area of interest in the study of heat and mass transfer. This study employs colored plots to analyze the optimum heat transfer over a double porous plate by altering different physical parameters. Using the shooting technique, the study provides numerical solutions to nonlinear systems of equations by transforming the partial differential equations (PDE) into ordinary differential equations (ODEs) via the dimensionless similarity transformation. Tables and graphs demonstrate how the governing parameters impact velocity, temperature, mass concentration profiles, and motile microorganisms, as well as physical quantities like skin friction coefficient, Nusselt number, Sherwood number, and motile number. Ternary hybrid ferrofluid exhibits a significantly improved heat transfer rate compared to both Ferro and hybrid ferrofluid. The convective flux of heat and mass transfer experiences a decrement with an escalation in the values of the activation energy (E) parameter. The presence of positive values for both the similarity variable (n) and Exothermic/Endothermic parameter (λ) leads to an enhancement in the flow of thermal transfer on both porous surfaces. This research will have far-reaching implications in various fields, including coolant technology in the manufacturing industry, heat dissipation in electronic modules, high-performance computing cooling facilities, the automotive sector, and space applications. [ABSTRACT FROM AUTHOR]

AbstractThis study presents a comprehensive investigation into the intricacies of single-phase simulation concerning the behavior of fractal interfacial magnetized metallic chemical-reactive nanoparticles within fluid systems. The research focuses on unraveling the multifaceted phenomena associated with heat and mass transfer in complex nanoscale environments. To achieve this, we employ numerical techniques to address the intricate fluid flow problems that arise due to the presence of these nanoparticles. Fractal complexities are linked to critical phenomena, such as mixing and mass transport, at the turbulent/non-turbulent interface of shear layers and boundary layers. This study primarily concentrates on the phenomena of heat and mass transfer, with a focus on estimating thermal conductivity models that have significant impacts on the flow of metallic nanofluids under convective conditions. The combination of a high thermal conductivity model with a novel interfacial fractal theory reveals a substantial effect on heat and mass transfer enhancement. Furthermore, this research explores hybrid types of porous channel geometries under the combined influence of magnetohydrodynamics and chemical reaction mechanisms in the presence of metallic nanoparticles. A comprehensive numerical analysis of higher-order nonlinear differential equations is conducted, which exposes the flow field’s behavior concerning momentum, energy, and mass transfer. These insights are envisioned through single-phase simulations of nanofluids. The influence of the nanoparticles’ radius and diameter is found to play a significant role in thermal performance, with nanoparticles ranging from 1% to 8% exhibiting a notable impact on thermal conductivity. HighlightsA new mathematical relation of mass, as well as heat transfer for metallic-nanomaterial being affected by thermal conductivity (T.C.), has been established.The important role of the physical number is observed under the effect of T.C. and heat and mass transfer through orthogonal porous surfaces.An injection/suction, as well as an expansion/contraction phenomenon related to the porous surface is observed.A new mathematical relation of mass, as well as heat transfer for metallic-nanomaterial being affected by thermal conductivity (T.C.), has been established.The important role of the physical number is observed under the effect of T.C. and heat and mass transfer through orthogonal porous surfaces.An injection/suction, as well as an expansion/contraction phenomenon related to the porous surface is observed. [ABSTRACT FROM AUTHOR]

AbstractThis articles focus the dynamics of fluid conveying ternary solid particles, nano-layer, and magnetic field effects subject to porous disks. The magnetized ternary nanoparticles induced by Ferro and nano-layer are considered due to their unusual characteristics like extraordinary thermal conductivity, which are significant in advanced nanotechnology, heat exchangers, material sciences, and electronics. To avoid possible sedimentation of tiny particles, the motile microorganisms are also considered in the elaborated fluid problem. The main objective of this comprehensive study is the enhancement of heat transportation. In this study, we also investigate the physical dynamics of entropy generation, particularly emphasizing viscous dissipation related to joule heating effects. The mass transfer equation was employed to monitor the chemical interaction with diverse nanoparticles. The results of comparative and numerical validation agree well. The approach of stable and accurate numerical boundary value problem of fourth order code (bvp4c) is applied to solve the nonlinear system of ordinary differential equations. Many useful engineering results are summarized here, including the skin friction coefficient (Cf), Nusselt number (Nu), Sherwood number (Sh), and motile number (Nn). For both porous disks, several non-dimensional parameter effects are depicted graphically and tabulated. The results show that the increasing the number of nanolayer particles slows the rate of the temperature profile in both porous disks, associated with the expansion ratio, Reynolds number, and magnetic field number. Moreover, increasing the values of the density ratio number results in an increase in the flow of microorganisms profile in both porous disks. Increasing the values of the diffusivity parameters and the temperature difference enhances the flow of entropy generation. [ABSTRACT FROM AUTHOR]

Abstract In the current analysis, we delivered a computational approach to the 2D boundary layer heat and mass transfer flow of water-based nanofluids over a vertical cone saturated by porous media with heat generation/absorption, thermal radiation, chemical reactions, the Soret–Dufour number, viscous dissipation, and a magnetic field. The controlling partial differential equations are converted into devoid of dimensions form and numerically dealt with by Crank–Nicolson through an implicit finite difference approach. Specifically, the given parameters, such as volume fraction (ϕ), MHD-Magnetohydrodynamics (M), Soret/Dufour (Sr-Du), viscous dissipation (ϵ), chemical reaction (λ), thermal radiation (Rd), and heat blowing/suction (Δ), have an impact on boundary layer flow characteristics (velocity, temperature, concentration, drag coefficient, rate of heat transfer, and mass transfer rate) are thoroughly studied, and the outcomes are visually and tabulated to demonstrate the actual significance of the problem. [ABSTRACT FROM AUTHOR]