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This paper examines the thermal transfer attributes of ZnO-H2O Walter's-B nanoliquid flow alongside an upright cone in the bearing of slip mechanism, radiative heat flux, and non-uniform heat source. We adopted suitable similarities to convert the nonlinear PDEs into ODEs and solved the transformed governing system by employing the bvp5c solver package in Matlab software. The prime novelty of this research is to compute the effective thermal diffusivity of the nanoliquid via the Maxwell and Xue nanomodels. Further, simultaneous results are deliberated for Maxwell and Xue cases via pictorial outcomes under various controlling limitations, such as velocity slip, radiative heat flux, buoyancy, viscoelastic, and volume fraction of nanomaterial. The thermal transmission rate of nanoliquid reported by the Xue nanomodel is higher than the Maxwell nanomodel. Therefore, the Xue nanomodel effectively works to enhance the thermal conductivity of the liquids with viscoelastic nature. Further, this study is helpful in industrial processing, where control over heat transport is required. [ABSTRACT FROM AUTHOR]

Solar thermal energy is a versatile and sustainable form of energy. It has vast applications and can be used to reduce fossil fuel consumption. The sun's heat harnesses this renewable energy; therefore, the energy transmission rate plays a significant role here. This article gives the idea of a new geometric design of solar thermal collector tubes for multiple uses and materials to be used on the tube's outer layer to maximize heat absorption. For this purpose, we investigated velocity, temperature, and heat transfer rates due to different nanoparticle (Cu/Al 2 O 3 /GO) combinations. We assumed the flow of Newtonian/non-Newtonian nanofluids flowing through the coaxial region of the cylindrical shape solar tubes. Here, water and seawater are considered for the Newtonian case, and sodium alginate is regarded for the non-Newtonian case. The governing equations of the flow are converted into ODEs with the help of similarity variables and solved numerically using the Keller box method. The MATLAB code for the Keller box method has been developed to plot graphical results. The primary outcomes are exhibited through graphs and tables. It is perceived that the temperature and heat transfer rates in Newtonian and non-Newtonian fluids are enhanced due to the trihybrid (Cu + Al 2 O 3 +GO) combination. This work can be utilized in an evacuated solar thermal system and gives the idea to develop a sustainable solar thermal system for multipurpose usage. • A sustainable solar thermal system model for multipurpose usage. • Simultaneous outcomes for Newtonian and non-Newtonian cases. • Al 2 O 3 +GO nanomaterial combination enhances the sun's heat absorption rate. • The heat absorption rate of evacuated solar heater tubes can be improved with a Cu + Al 2 O 3 +GO + sea water combination. [ABSTRACT FROM AUTHOR]

Theoretical analysis is performed to examine the heat convection in hydromagnetic Sutterby nanofluid flow across a cone in the attendance of Darcy-Forchheimer and modified temperature flux effects. The enhanced heat transmission was investigated using Maxwell and interfacial layer (nanolayer) approaches by considering ethylene glycol (EG) based spherical copper (Cu) nanoparticles. An exact model is developed and verified numerically using the bvp5c MATLAB scheme. Simultaneous outcomes are obtained for Maxwell and nanolayer approaches. Pertinent parameters influence on momentum and energy fields is examined via plots and tables. The nanolayer approach reported higher thermal conductivity than the Maxwell approach. Also, modified heat flux commendably improves the heat diffusion rate of Sutterby nanofluid without affecting the wall resistance. [ABSTRACT FROM AUTHOR]

We analyzed the momentum and heat transfer characteristics of unsteady MHD flow of a dusty nanofluid over a vertical stretching surface in presence of volume fraction of dust and nano particles with non uniform heat source/sink. We considered two types of nanofluids namely Ag-water and Cu-water embedded with conducting dust particles. The governing equations are transformed in to nonlinear ordinary differential equations by using similarity transformation and solved numerically using Shooting technique. The effects of non-dimensional governing parameters on velocity and temperature profiles for fluid and dust phases are discussed and presented through graphs. Also, the skin friction coefficient and Nusselt number are discussed and presented for two dusty nanofluids separately in tabular form. Results indicate that an increase in the volume fraction of dust particles enhances the heat transfer in Cu-water nanofluid compared with Ag-water nanofluid and a raise in the volume fraction of nano particles shows uniform heat transfer in both Cu-water and Ag-water nanofluids.

In this paper, a numerical computational work is carried out to investigate the significance of nanoparticle shape on magnetohydrodynamic stagnation-point flow of Carreau nanoliquid caused by a horizontally moving thin needle. The drive and thermal transport nature of Ti6Al4V+Ethylene glycol nanoliquid under the stimulus of space-dependent heat source and magnetized force is discussed numerically. The novelty of this work is to obtain the simultaneous solutions for three different shapes of nanoparticles namely spherical, cylindrical and laminar. The flow governing partial differential equations are transformed into ordinary differential equations with appropriate similarity variables and solved numerically by using Runge–Kutta and Newton's approach. Numerical outcomes of velocity and thermal distributions under the influence of different physical parameters are illustrated via graphical trends, wall friction and rate of heat transfer are interpreted using tabular values. It reveals from results that the thermal transfer performance of the Carreau nanoliquid is advanced when spherical shaped nanoparticles are used as compared with cylindrical and laminar-shaped nanoparticles. Also, it is witnessed that needle thickness parameter plays vital role in augmenting thermal transport rate of the nanoliquid. [ABSTRACT FROM AUTHOR]

The flow and energy transport of water-ethylene glycol (EG) based Ti-Cu hybrid nanofluid due to incessantly poignant needle in magnetohydrodynamic Sakiadis flow with resistive heating is investigated. We scrutinized the flow and heat transfer of the Blasius and free stream flows. The governing Partial Differential Equations are transformed as Ordinary Differential Equations using suitable similarities and resolved numerically using RK (Runge-Kutta) based shooting procedure. Numerical and graphical outcomes are explored and examined for the drive, thermal transport, surface friction and local Nusselt number of various pertinent parameters. It is originate that the flow and thermal boundary layer of Blasius and Sakiadis flows are not equal. The rate of energy transport is high in moving needle in the static fluid when equated with the fixed needle in dynamic fluid. It is also established that the rate of heat transfer in Ti-Cu/EG-water hybrid nanofluid is more than water-EG/Ti nanofluid. [ABSTRACT FROM AUTHOR]

This study reports the enhanced heat transfer of electrically conducting magnetic-nanofluids with thermal radiation and inclined magnetic field effects. We consider water as a base fluid embedded with the two different types of aluminum alloy nanoparticles namely AA 7072 and AA 7075. AA 7072 is a special type of heat treatable aluminum alloy with 98% Al and 1% of Zn with the additives such as Si , Fe and Cu . Similarly, AA 7075 contains 90% Al , 5–6% Zn , 2–3% Mg , 1–2% Cu with the additives such as Si, Fe and Mn . Numerical results are explored with the aid of R-K and Newton’s techniques. Results are depicted diagrammatically and discussed on the common profiles of interest (velocity and temperature). The heat transfer rate of water-AA 7075 nanofluid is significantly high when compared with the rate of heat transfer of water-AA 7072 nanofluid. [ABSTRACT FROM AUTHOR]

Extrinsic magnetic fields are capable to set the thermal and physical properties of magnetic-nanofluids and regulate the flow and heat transfer characteristics. Applied magnetic field affects the thermal conductivity of magnetic-nanofluids and makes it aeolotropic. With this incentive, we investigate the flow and heat transfer characteristics of liquid film flow of magnetic-nanofluids over the vicinity of a thin elastic sheet by considering the transverse magnetic field with variable heat source/sink. We consider water as a base fluid embedded with the two different types of aluminum alloy nano/particles namely AA 7072 and AA 7075. AA 7072 is a special type of heat treatable aluminum alloy with 98% Al and 1% of Zn with the additives such as Si, Fe and Cu etc. Similarly, AA 7075 contains 90% Al, 5–6% Zn, 2–3% Mg, 1–2% Cu with the additives as Si, Fe and Mn etc. The transformed governing partial differential equations are solved numerically using R-K based shooting technique. The diagrammatic and tabular results depict the effect of pertinent parameters on common profiles of interest. It is found that the heat transfer rate of water-AA 7075 is significantly high when compared with the heat transfer rate of water-AA 7072. It is also found that the increasing percentage of Cu leads to enhance the heat transfer rate. [ABSTRACT FROM AUTHOR]

Nowadays graphene is emanating as one of the most encouraging nanomaterial due to its continuous electrical conducting behaviour even at zero carrier concentration. With this initiation, we investigate the flow and heat transfer nature of liquid film flow of magnetic-nanofluids over a stretching surface by considering the aligned magnetic field with non-uniform source/sink and thermal radiation. For this study, we considered the graphene (GP) nanoparticles embedded in water and water-ethylene glycol (EG) mixtures (i.e. 70%water + 30%EG and 50%water + 50%EG). With the assistance of similarity transformations, governed equations are transferred as ordinary differential equations. Numerical results are determined by applying the Runge-Kutta and Newton’s methods. Graphs are exhibited and explained for important parameters. The influence of non-dimensional parameters on reduced Nusselt number, flow and heat transfer is discussed with the assistance of graphs. It is found that aligned magnetic field regulates the local Nusselt number. It is also found that rising the volume fraction of nanoparticles effectively boosts the thermal conductivity of water + 50%EG + GP nanofluid when compared with water + GP and water + 30%EG + GP nanofluids. [ABSTRACT FROM AUTHOR]

With every passing day, heat transfer enhancement in convectional base fluids plays a major role in several industrial and engineering processes. During this process, nanofluids attained great importance to enhance the heat transfer rate in convectional flows. Keeping this into view, in this study, we analyzed the MHD flow and heat transfer characteristics of a dusty nanofluid over a stretching surface in the presence of a volume fraction of dust and nano-particles. We have considered two types of nanofluids; namely, CuO-water and Al2O3-water immersed with dust particles. The governing partial differential equations are transformed into a set of nonlinear ordinary differential equations by using similarity transformation, which are then solved numerically using Runge-Kutta based shooting technique. We found an excellent agreement of the present results with the existing literature. The effects of non-dimensional governing parameters; namely, magnetic field, volume fraction of dust particles, volume fraction of nano-particles, porosity, mass concentration of dust particles and fluid particle interaction on velocity and temperature profiles for both fluid and dust phases are discussed and presented through graphs. Also, skin friction coefficient and local Nusselt number are discussed and presented in tabular form. [ABSTRACT FROM AUTHOR]

The motion of nanofluid (water and 36 nm alumina nanoparticles) along upper horizontal surface of a paraboloid of revolution in the presence of nonlinear thermal radiation, Lorentz force and space dependent internal heat source within thin boundary layer is investigated theoretically. It is assumed that buoyancy induces the flow over this kind of surface which is neither a horizontal/vertical nor cone/wedge, hence suitable buoyancy model for this case of fluid flow is presented. The viscosity and thermal conductivity are assumed to vary with volume fraction and suitable models for the case 0 % ≤ ϕ ≤ 0.8% are adopted. The transformed governing equations are solved numerically using Runge-Kutta fourth order along with shooting technique (RK4SM). Good agreement is obtained between the solutions of RK4SM and MATLAB bvp5c for limiting case. The influence of pertinent parameters are illustrated graphically and discussed. It is found that temperature and velocity functions are maximum at higher values of internal space dependent heat source. Local heat transfer rate is maximum at smaller values of internal space dependent heat source. [ABSTRACT FROM AUTHOR]

This paper deals with the momentum, heat and mass transfer behaviour of MHD nanofluid flow embedded with conducting dust particles past an inclined permeable stretching sheet in presence of radiation, nonuniform heat source/sink, volume fraction of nano particles, volume fraction of dust particles and chemical reaction. We have considered Cu-water nanofluid embedding with conducting dust particles. The governing partial differential equations of the flow, heat and mass transfer are transformed into nonlinear ordinary differential equations by using similarity transformation and solved numerically using Runge-Kuttabased shooting technique. The effects of non-dimensional governing parameters on velocity, temperature and concentration profiles are discussed with the support of graphs. Also, skin friction coefficient, Nusselt and Sherwood numbers are discussed and presented through tables. Under some special conditions present results have good agreement with the existed results. It is observed a raise in the heat transfer rate due to increase in the fluid particle interaction parameter. It is also observed that an increase in chemical reaction parameter enhances the mass transfer rate of the dusty nanofluid. [ABSTRACT FROM AUTHOR]

A theoretical analysis is performed to investigate the free convective heat and mass transfer in three-dimensional magnetohydrodynamic slip flow of a nanofluid over a slendering (variable thickness) stretching sheet in the presence of thermophoresis and Brownian motion effects. Our considerations are water as base fluid, graphene and magnetite as nanoparticles and we did the simultaneous study of them on various profiles. R-K-Felhberg-integration scheme is employed to resolve the altered governing nonlinear equations. Influences of the parameters of concern on the common profiles (velocity, temperature, concentration) are conversed (in two cases). By viewing the same parameters, the skin friction coefficient, heat and mass transfer are discussed with the assistance of tables in two instances. It is found that the momentum, thermal and concentration boundary layers of water-graphene and water-magnetite nanofluids are non-uniform. It is also found that the rate of heat and mass transfer is high in water-graphene nanofluid when compared with the water-magnetite nanofluid. [ABSTRACT FROM AUTHOR]

Nanofluids are potential heat transfer fluids with enhanced thermal and physical properties. In particular, the fluids embedded with titanium nanoparticles have tendency to control the heat transfer mechanism in surgical implant applications such as glass covering of iris, retina and glaucoma etc. External magnetic fields are capable to set the thermal and physical properties of magnetic-nanofluids and regulate the flow and heat transfer characteristics. With this incentive, a theoretical investigation is performed for exploring the flow and heat transfer behavior of magneto-nanofluids caused by a rotating cone in the presence of temperature dependent viscosity and heat source/sink. For this study, we considered Ti and Ti-alloy (Ti6Al4V is a titanium alloy with 90% titanium, 6% aluminum and 4% Vanadium) nanoparticles embedded in water. With the aid of similarity variables, we transformed the governing equations as ordinary differential equations and numerical solutions are found by employing Runge-Kutta and Newton's methods. We discussed the friction factor coefficients, local Nusselt number, flow and heat transfer performance of both nanofluids with the assistance of graphs and tables. We found that the heat transfer performance of Ti-water nanofluid is high when compared with the heat transfer performance of Ti-alloy water nanofluid. From this we can conclude that Ti-alloy combination nanofluids are useful for cooling processes. [ABSTRACT FROM AUTHOR]

The present report covers the investigation of three-dimensional MHD nanofluid flow over a slendering (variable thickness) stretching sheet bearing thermophoresis, Brownian motion and slip effects. For this investigation, we considered water based Cu and CuO nanofluids. With the assistance of similarity transformations, we changed the derived governed equations as ordinary differential equations. The mathematical results determined by employing Runge-Kutta and Newton’s methods. We exhibit and explain the graphs for various parameters of interest. We discussed the skin friction coefficient, reduced Nusselt and reduced Sherwood numbers for the influence of the pertinent parameters with the assistance of tables separately for two nanofluids. (Cu-water and CuO-water). Results are validated by comparing with the published results and found a favorable agreement. [ABSTRACT FROM AUTHOR]

This is a theoretical investigation on the Brownian motion and thermophoresis effects on the flow, heat and mass transfer in magnetohydrodynamic Jeffrey, Maxwell and Oldroyd-B nanofluids over a cone in the presence of non-uniform heat source/sink effects and variable magnetic fields. The transformed systems of nonlinear ordinary differential equations are solved numerically. Buongiorno's two-component heterogeneous model is used for the nanofluids in the hypothesis that nanoparticles have slip velocity relative to the base fluid, originating from the Brownian motion and thermophoresis. The effects of various non-dimensional governing parameters on the flow, heat and mass transfer are discussed with the help of graphs and tables. A good agreement is obtained between the present results and the ones exist in literature. It is observed that Maxwell nanofluid is highly influenced by the magnetic field while compared with the Jeffrey and Oldroyd-B nanofluids. In addition, the non-uniform heat source/sink parameter acts like a major controlling parameter of the nanofluid flow and heat transfer rate. Furthermore, the heat transfer rate of Jeffrey nanofluid is significantly stronger than the one of Oldroyd-B and Maxwell nanofluids. [ABSTRACT FROM AUTHOR]

In this study we analyzed the magnetohydrodynamic forced convective flow of a nanofluid over a slendering stretching sheet in porous medium in presence of thermal radiation and slip effects. We presented dual solutions for no-slip and Navier slip conditions. Using self similarity transformation, the governing partial differential equations are transformed into nonlinear ordinary differential equations and solved numerically using BVP5C Matlab package. The effects of dimensionless governing parameters on velocity and temperature profiles of the flow are discussed with the help of graphs. Numerical computations are carried out and discussed for skin friction coefficient and local Nusselt number. We found an excellent agreement of the present results with the existed results under some special conditions. Results indicate that the dual solutions exist only for certain range of velocity slip parameter. It is alsofound that the heat transfer performance is high in presence of velocity slip effect. [ABSTRACT FROM AUTHOR]

AbstractSolar energy is an essential source of clean, renewable energy that has the potential to transform our energy system and reduce impact on the environment. But, only 3.6% of solar energy is effectively used around the globe for electricity generation. So, using solar energy to the maximum extent is essential to control air pollution and save the environment for future generations. This article discusses the operative use of solar energy and suggests measures for optimal solar energy utilization in electric vehicles (EVs). The water-based silicon dioxide (SiO2) and aluminum oxide (Al2O3) combination is considered due to the high refractive index of SiO2 and scratch resistance and durability of Al2O3. A theoretical model was established by considering the shape of the solar collector, temperature change, nano spray, and radiative heat. The modeled problem was computationally resolved using the bvp5c MATLAB scheme, and simultaneous results were explored for various outlines of solar collectors. It is found that the shape of the solar collector and nanospray/nanocoating play a significant role in the practical usage of solar energy. Using curved-shaped solar collectors with water-SiO2-Al2O3 nanocoating allows the solar collector to absorb more light. This helps to improve the effectiveness of solar collectors in running EVs, which can reduce carbon growth. [ABSTRACT FROM AUTHOR]

A theoretical analysis of unsteady, three-dimensional stagnation-point flow of Al–Cu nanoparticle suspended water based nanofluid is performed. The thermophysical properties of alloy nanoparticles like density, specific heat capacity and thermal conductivity are computed using appropriate formula. A micro-convection based model framed by Patel et al. [1] is used for predicting the thermal conductivity of nanofluid. The governing physical model is mathematically modeled into a set of non-linear parabolic partial differential equations and solved by a shooting technique. A parametric study is performed for a varied range of nanoparticle volume fraction, ratio of the velocity gradient, unsteadiness parameter and the magnetic parameter. Additionally, the importance of the different compositional characteristics of the alloy nanoparticles on the flow and the thermal field is also examined. It is observed that the Nusselt number increases as the unsteadiness parameter λ decreases and the ratio of the velocity gradient c increases in the nodal point region. A novel result of the analysis reveals that the highest skin friction is obtained for Al 50 Cu 50 - water and the highest Nusselt number is obtained for Al 90 Cu 10 -water. [ABSTRACT FROM AUTHOR]

The boundary layer analysis of a 2D forced convection flow along an incessant moving horizontal needle in magnetohydrodynamic radiative nanofluid is investigated. The energy equation is incorporated with the joule heating, non-constant heat source/sink, and viscid dissipation effects. To check the variation in the boundary layer nature, we considered the two nanofluids namely, Ag–water and Ag–Kerosene. The reduced system of governing PDEs is solved by employing the Runge–Kutta Fehlberg integration scheme. Computational results of the local Nusselt number and friction factor are tabulated and discussed. Velocity and temperature fields are discussed with the help of graphical illustrations. Increasing the needle size significantly reduces the flow and energy boundary layers of both nanofluids. In particular, thermal and velocity fields of Ag–kerosene nanofluids are highly dissed when equated with the Ag–water nanofluid. [ABSTRACT FROM AUTHOR]

In the industry, the thickness of many surfaces can be described as non-uniform. To a reasonable extent, an upper half surface of a horizontal object with variable thickness can be described as a paraboloid of revolution. In this article, a modified version of a buoyancy-induced model is considered to account for the force which drives the flow of 29 nm CuO -water nanofluid along its upper horizontal surface in the presence of nonlinear thermal radiation. The case of unequal diffusion coefficients of reactant A (bulk fluid) and B (high concentration of catalyst at the surface) in the presence of a gyrotactic microorganism is considered. It is assumed that there exist a significant difference between nanoparticle mass density and base fluid density. Governing equation suitable to unravel the thermophoresis which takes place within the boundary layer is presented. Since chemical reactant, B is of higher concentration at the surface more than the concept earlier described as cubic autocatalytic, hence the suitable schemes herein described as isothermal quartic autocatalytic reaction and first order reaction. The dynamic viscosity and thermal conductivity are assumed to vary with volume fraction ( ϕ ) and suitable models for the case 0 ≤ ϕ ≤ 0.9 are adopted. The transformed governing equations are solved numerically using Runge-Kutta fourth order along with shooting technique (RK4SM). Good agreement is obtained between the solutions of RK4SM and MATLAB bvp5c for a limiting case. Numerical analysis of many emerging parameters is illustrated graphically and discussed. [ABSTRACT FROM AUTHOR]

Nowadays, the foremost thermal source from the sun is solar energy. The current study deals with the enhanced heat transfer of Parabolic Trough Solar Collector (PTSC) using thermic radiation, space-dependent heat source, and nanotechnological energy. For this, we considered water-based graphene oxide (GO) and alumina alloy (AA7075) mixtures flow through PTSC fitted inside the solar wings of aircraft (Fig. 1). A theoretical Maxwell nano model is adopted by incorporating the thermic radiation and space-dependent heat source/sink effects in the energy equation. The pressure drop caused by the fluid-solid interactions is evaluated by introducing the Darcy-Forchheimer condition. The modeled problem is resolved numerically by applying suitable similarities. The impact of various physical constraints on flow and thermal fields are estimated for water-GO and water-GO-AA7075 fluids and found that water-GO-AA7075 hybrid nanoliquid effectively enhances the thermal performance of PTSC in the presence of thermic heat. Darcy-Forchheimer parameter effectively regulates the momentum and energy fields of hybrid nanoliquid. • Enhanced heat transfer efficiency of Parabolic Through Solar Collector (PTSC). • Usage of solar power for energy storage applications. • The Darcy-Forchheimer condition evaluates pressure drop caused by the fluid-solid interactions. • Water-GO-AA7075 hybrid nanoliquid effectively enhances the thermal performance of PTSC in the presence of thermal radiation. • A nanotechnology application for hydrogen energy storage. [ABSTRACT FROM AUTHOR]