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The influence of thermal radiation and Joule heating on the entropy inception by triple diffusion over the permeable plate is examined, as well as its influence on other physical aspects of the problem. The radiative and Joules heating effects are being investigated using a mathematical model. The irreversibility caused variations in entropy inception due to fluid, heat fluxes, and solute concentration of salts utilized. The non-dimensioned modeled equations were interpreted numerically by shooting approach using Runge-Kutta-Fehlberg scheme. Numerical outcomes were plotted in the form of graphs for flow and thermal distributions, entropy inception rate, and Nusselt number because of suction/injection through the plate, and the results of concentration based parametric analysis were plotted out for local entropy inception rate, local Bejan number, local mass Bejan number and local irreversibility ratio based on assisting flow and opposing flow. Local mass Bejan number underwent some interesting aspects, such that it behaves opposite to local Bejan number to enhance for magnetic, radiation parameter in suction/injection situations. In the suction/injection flow conditions, the entropy inception rate gets enhanced for most of the flow and thermal parameters like magnetic, radiation, convective parameters, Eckert number, buoyancy parameters of solutes 1 and 2, and temperature ratio parameter. Because of influences of assisting and opposing flow, the entropy inception rate gets slowed down by the effects of Lewis numbers of solutes 1 and 2 and Darcy number. Reynolds number has the influence assisting the entropy rate to increase. [ABSTRACT FROM AUTHOR]

This paper aims to examine the effects of singleand multi‐walled carbon nanotubes (CNTs) nanoparticles on heat transfer enhancement and inherent irreversibility in the boundary layer of water base nanoliquid flow over a convectively heated moving wedge with thermal radiation. Manipulation of the angle positioning towards the flow stream provides the opportunity for comparing physical aspects in the flow states, where three main geometries of the well‐known Falkner–Skan problem include: (i) the flat plat (named Blasius flow), (ii) the wedge, and (iii) the vertical plate (named Hiemenz stagnation flow) have been considered to present a comprehensive development of this significant problem. Applying suitable similarity constraints, the model partial differential equations are transformed into a set of nonlinear ordinary differential equations. Solutions are obtained analytically via optimal homotopy asymptotic method and numerically via shooting technique coupled with the Runge–Kutta–Fehlberg fourth–fifth scheme. The impacts of solid volume fraction of carbon nanoparticles along with other germane factors, such as wedge angle, velocity ratio parameter, Biot number, thermal radiation, and so forth on velocity and thermal profiles, Nusselt number, heat transfer enhancement, rate of entropy generation, and irreversibility ratio, are scrutinized via graphical simulations and discussed. Optimization of such entropy developments in the system was found to depend on geometrical (β), dynamical (λ), and thermophysical (Bi, NR, Ec, φ) parameters. The ultimate objective of reducing the energy loss and enhancing heat transference was obtained with the geometrical manipulation of a flat plate case (β = 0). Dynamically (λ = 1) were spotted to exert the best fluidity irrespective of obstacle shapes (wedge or plate) in its way. In thermophysical aspects, reducing the convective heating develops a favorable situation for attaining the optimal balance between energy loss and heat transfer. SWCNT/water could be the better choice with enhanced thermal transference ability and exerts minimal irreversibility to overshadow the influences of all the above‐mentioned factors. The SWCNT suspended nanofluid can provide 12%–64% heat transfer enhancement when compared with the multiwalled CNT nanofluid which ranges from over 11% to 58% heat transference rate. [ABSTRACT FROM AUTHOR]

For heating, ventilation or air conditioning purposes in massive multistory building constructions, ducts are a common choice for air supply, return, or exhaust. Rapid population expansion, particularly in industrially concentrated areas, has given rise to a tradition of erecting high-rise buildings in which contaminated air is removed by making use of vertical ducts. For satisfying the enormous energy requirements of such structures, high voltage wires are used which are typically positioned near the ventilation ducts. This leads to a consequent motivation of studying the interaction of magnetic field (MF) around such wires with the flow in a duct, caused by vacuum pump or exhaust fan etc. Therefore, the objective of this work is to better understand how the established (thermally and hydrodynamically) movement in a perpendicular square duct interacts with the MF formed by neighboring current-carrying wires. A constant pressure gradient drives the flow under the condition of uniform heat flux across the unit axial length, with a fixed temperature on the duct periphery. After incorporating the flow assumptions and dimensionless variables, the governing equations are numerically solved by incorporating a finite volume approach. As an exclusive finding of the study, we have noted that MF caused by the wires tends to balance the flow reversal due to high Raleigh number. The MF, in this sense, acts as a balancing agent for the buoyancy effects, in the laminar flow regime [ABSTRACT FROM AUTHOR]

Numerical analysis is performed for an incompressible Marangoni Maxwell nanofluid flow model under the implications of thermophoresis, brownian motion and nonlinear radiation over a convectively heated rotating disk. The second law of thermodynamics is also incorporated. The system that comprises differential equations of partial derivatives is remodeled into the system of differential equations via similarity transformations and then solved numerically through the Runge-Kutta-Fehlberg with shooting technique. The physical parameters, which emerges from the derived system are discussed in graphical formats. The significant outcomes of the current investigation are that the velocity filed decays for a higher magnetic parameter, the heat transfer rate is enhanced with the incremental values of radiation parameter and Prandtl number. Further, the entropy generation rate decreases with the fluid parameter while that peters out the Bejan number. [ABSTRACT FROM AUTHOR]

Fluidity and thermal transport across the triangular aperture with lower lateral inlet and apply placed at the vertical outlet of the chamber which filled with efficient TiO2–SiO2/water hybrid nanofluid under the parametrical influence. Several parameters are tested like the numbers of Hartmann ( 0 ≤ H a ≤ 100 ), Richardson ( 0 ≤ R i ≤ 5 ), and Reynolds ( 10 ≤ R e ≤ 1000 ) were critiqued through streamlines, isotherms, and Nusselt number ( Nu ). Numerical model has to be developed and solved through the Galerkin finite element method (GFEM) by discretized with 13,569 triangular elements optimized through grid-independent analysis. The Hartmann number ( Ha ), exerts minimal impact over the flow and thermal aspects while the other parameters significantly manipulate the physical nature of the flowing and thermal aspects behaviors. [ABSTRACT FROM AUTHOR]

The thermal control subject of heat transference encompasses the generation, use, conversion, and transportation of thermal energy. Heat transference is critical in engineering and industrial industries such as food processing, food additive manufacturing, electronic cooling, microturbines, and so on. Because of the intriguing possibilities in sectors such as polymer manufacture, paper production, crystal glass manufacturing, and so on, academics all over the globe have attempted to investigate the influence of heat transmission on fluid past an expanding surface. We constructed a symmetric system relating extended Burgers' nanofluid (BNF) with Fourier's and Fick's laws in a symmetric stretchy slip as part of our investigation. The Cattaneo-Christov mass and heat diffusions principle has been considered. The Buongiorno occurrence is also utilized for the symmetric flowing of nanofluids (NFs) in the generalized Burger's fluid, according to the Cattaneo-Christov connection (CCC). For the numerical solution, using the similarity transformations, the control system that regulates partial differential equations (PDE) was turned into ordinary differential equations (ODE). Using the COMSOL program, the Galerkin finite element method (G-FEM) is utilized to generate mathematical results for non-linear equations. We observed greater temperature and concentration for Fourier-Fick's conditions as compared to revised Fourier-Fick's scenarios. The heat field is raised to produce the calculations of the current Biot quantity and generalized BNF factor. To receive results in the form of figures and tables, the parameter values must be between 0.1 ≤ β 1 ≤ 0.5, 0.2 ≤ β 2 ≤ 0.4, 0.2 ≤ β 3 ≤ 0.4, 0.2 ≤ β 4 ≤ 0.4, 0.1 ≤ M ≤ 1.2, 0.1 ≤ Nr ≤ 0.9, 0.1 ≤ λ ≤ 0.5, 0.2 ≤ K ≤ 1.6, 0.1 ≤ Rd ≤ 1, 0.1 ≤ λ T ≤ 0.3, 0.1 ≤ δ 1 ≤ 0.3, 0.1 ≤ E ≤ 1 and 0.1 ≤ Le ≤ 0.9. The G-FEM investigation of Burgers' nanofluid (BNF) in the presence of heat source, thermal radiative heat flux and Cattaneo-Christov mass and heat flux has not been investigated yet in the available literature. [ABSTRACT FROM AUTHOR]