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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]

The present article emphasizes the bearing of radiative heat flux, Joule heating on the 3D magneto-flow of tangent hyperbolic mixed nanoliquid above a linear/nonlinear expandable surface. The aluminum alloy nanoparticles AA7072 and AA7075 are suspended in methanol liquid to obtain a hybrid nanofluid. The nonlinear partial differential equations are renovated to ordinary differential equations by utilizing appropriate similarity conversions, and further, the solutions are attained via the bvp5c MATLAB package. The novelty of this research is to supply simultaneous outcomes of the radiative hydrodynamic flow along linear and nonlinear extending surface situations. Further, the stimulus of sundry factors on the flow features is reflected with the aid of plots. The thermal transport rate in the nonlinear extending case is twice greater than the linear stretching case under the action of nanoparticles. Also, the existence of unique nanoparticles performs a substantial response in boosting the thermal transport mechanism of the non-Newtonian liquid. [ABSTRACT FROM AUTHOR]

The silver and gold nanoparticles display noteworthy results in antimicrobial and anticancer therapies. Silver is a considerable anti-inflammation, and gold nanoparticles effectively use to convert the photons to heat to destroy cancer cells. By keeping this in view, we investigated the radiative heat allocation in blood-based Ag-Au hybrid nanofluid flow. We assumed a blood vessel with cosine stenosis in the existence of an aligned magnetic field and variable heat source/sink. The flow model was developed to investigate the underlying physics and solved numerically after applying appropriate transformations. The computational outcomes for the flow and energy fields were explored through graphical and numerical illustrations. Also, the consequences of local Nusselt number and wall friction were discussed. The outcomes are validated and found to be in noble agreement. It is noticed that the inclined magnetic angle can control the drag force and heat transmission. Also, the Ag-Au combination effectively enhances the rate of heat transfer. This may help the effective conversion of photons to heat energy used in cancer therapies. [ABSTRACT FROM AUTHOR]

The pivotal aim of this research is to address the boundary layer analysis of two-dimensional unsteady hybrid nanofluid flow over a flat/slendering stretching surface. Thermal radiation and magnetohydrodynamic analysis are featured in this work. The transformed nonlinear ordinary differential equations are resolved using Runge–Kutta–Fehlberg technique. Then, a complete discussion of the influences of the flow regime on several thermofluidic parameters is presented. The significant outcome of the current investigation is that the increment in magnetic field and nanoparticle volume fraction parameters declines the skin friction. Furthermore, it is shown that when the radiation and the nanoparticle volume fraction are improved, the heat transfer rate triggers considerable evolution. The obtained results of this model closely match with those available in the literature as a limiting situation. [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]

White crystalline powder (aluminum oxide-Al2O3) and water are the products often formed after the heating of aluminum hydroxide. In this report, boundary layer flow of two different nanofluids (i.e., 36 nm Al2O3-water and 47 nm Al2O3-water) over an upper horizontal surface of a paraboloid of revolution under the influence of magnetic field is presented. The combined influence of magnetic field strength, electric current density, electric charge, electron collision time, and the mass of an electron in the flows are considered in the governing equations. Three-dimensional transport phenomenon was considered due to the influence of the Lorentz force (F→) along the z-direction as in the case of Hall currents. In this study, the dynamic viscosity and density of the nanofluids are assumed to vary with the volume fraction ϕ. The dimensional governing equations were non-dimensionalization and parametrization using similarity variables. The corresponding boundary value problem was transformed into initial value problem using the method of superposition and solved numerically using fourth-order Runge-Kutta method with shooting technique (RK4SM). Magnetic field parameter is seen to have dual effects on the cross-flow velocity profiles of both nanofluids. The maximum cross-flow velocity is attained within the fluid domain when 36 nm nanoparticles alumina is used. The cross-flow velocity gradient at the wall increases with magnetic field parameter (M) and also increases significantly with Hall parameter at larger values of M. [ABSTRACT FROM AUTHOR]

The 3D flow of non-Newtonian nanoliquid flows past a bidirectional stretching sheet with heat transfer is investigated in the present study. It is assumed that viscosity of the liquid varies with temperature. Carreau non-Newtonain model, Tiwari and Das nanofluid model are used to formulate the problem. The impacts of Joule heating, nonlinear radiation and non-uniform (space and temperature dependent) heat source/sink are accounted. Al-Cu-CH3OH and Cu-CH3OH are considered as nanoliquids for the present study. The solution of the problem is attained by the application of shooting and R.K. numerical procedures. Graphical and tabular illustrations are incorporated with a view of understanding the influence of various physical parameters on the flow field. We eyed that using of Al-Cu alloy nanoparticles in the carrier liquid leads to superior heat transfer ability instead of using only Aluminum nanoparticles. Weissenberg number and viscosity parameter have inclination to exalt the thermal field. [ABSTRACT FROM AUTHOR]

Abstract The boundary layer analysis of liquid film flow of ferrofluids has awesome consideration due to its inexhaustible pragmatic applications in manufacturing processes. By keeping this in view, we analyzed the magnetohydrodynamic film flow of Casson fluid past an extending sheet with thermal radiation and non-uniform heat source/sink. To investigate the magnetic field effect on the flow, we applied the magnetic field at various flow directions. Dual solutions are found for kerosene-Fe 3 O 4 and kerosene-CoFe 2 O 4 ferrofluids. Similarity transformations are used to convert the nonlinear PDE's as a group of nonlinear ODE's. R-K strategy based shooting technique is utilized to solve the converted equations. Numerical estimations of the physical parameters involved in the problem are calculated for the friction factor and reduced Nusselt number. It is noticed that the heat transfer rate is high in kerosene-Fe 3 O 4 ferrofluid when compared to kerosene-CoFe 2 O 4 ferrofluid. [ABSTRACT FROM AUTHOR]

Abstract The present study deals with the boundary layer analysis of a 2 D magnetohydrodynamic flow of chemically reacting Casson nanofluid flow over a semi-infinite inclined porous plate. The energy and diffusion equation are encompassed with frictional heating, heat generation/absorption, thermo diffusion and thermal radiation effects. For making the analysis more attractive we pondered two distinct type of nanofluids namely, TiO 2 -water and CuO-water. The transmuted governing PDEs are resolved analytically by employing regular perturbation method. The impact of pertinent flow parameters on momentum, thermal and mass transport behavior including the skin friction factor, thermal and mass transport rate are examined and published with the assistance of graphical and tabular forms. Results describe that thermal radiation and chemical reaction restrictions have a propensity to enhance thermal and mass transport rates, respectively. And also, water based TiO 2 nanofluid possess higher velocity compared with water based CuO nanofluids. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to provide an insight into the influence of gyrotactic microorganisms and Hall effect on the boundary layer flow of 29 nm CuO-water mixture on the upper pointed surface of a rocket, over the bonnet of a car and upper pointed surface of an aircraft. This is true since all these objects are examples of an object with variable thickness.Design/methodology/approach The simplification of Rosseland approximation (Taylor series expansion of T4 about T∞) is avoided; thus, two different parameters relating to the study of nonlinear thermal radiation are obtained. The governing equation is non-dimensionalized, parameterized and solved numerically.Findings Maximum vertical and horizontal velocities of the 29 nm CuO-water nanofluid flow is guaranteed at a small value of Peclet number and large value of buoyancy parameter depending on the temperature difference. When the magnitude of thickness parameter χ is small, cross-flow velocity decreases with the velocity index and the opposite effect is observed when the magnitude of χ is large.Originality/value Directly or indirectly, the importance of the fluid flow which contains 29 nm CuO nanoparticle, water, and gyrotactic microorganisms in the presence of Hall current has been pointed out as an open question in the literature due to its relevance in imaging, ophthalmological and translational medicine informatics. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to scrutinize the effects of nonlinear thermal radiation and thermal stratification effects on the flow of three-dimensional Eyring-Powell 36 nm alumina-water nanofluid within the thin boundary layer in the presence of quartic autocatalytic kind of chemical reaction effects, and to unravel the effects of a magnetic field parameter, random motion of the tiny nanoparticles and volume fraction on the flow.Design/methodology/approach The chemical reaction between homogeneous (Eyring-Powell 36 nm alumina-water) bulk fluid and heterogeneous (three molecules of the catalyst at the surface) in the flow of magnetohydrodynamic three-dimensional flow is modeled as a quartic autocatalytic kind of chemical reaction. The electromagnetic radiation which occurs within the boundary layer is treated as the nonlinear form due to the fact that Taylor series expansion may not give full details of such effects within the boundary layer. With the aid of appropriate similarity variables, the nonlinear coupled system of partial differential equation which models the flow was reduced to ordinary differential equation boundary value problem.Findings A favorable agreement of the present results is obtained by comparing it for a limiting case with the published results; hence, reliable results are presented. The concentration of homogeneous bulk fluid (Eyring-Powell nanofluid) increases and decreases with ϕ and Pr, respectively. The increase in the value of magnetic field parameter causes vertical and horizontal velocities of the flow within the boundary layer to decrease significantly. The decrease in the vertical and horizontal velocities of Eyring-Powell nanofluid flow within the boundary layer is guaranteed due to an increase in the value of M. Concentration of homogeneous fluid increases, while the concentration of the heterogeneous catalyst at the wall decreases with M.Originality/value Considering the industrial applications of thermal stratification in solar engineering and polymer processing where the behavior of the flow possesses attributes of Eyring-Powell 36 nm alumina-water, this paper presents the solution of the flow problem considering 36 nm alumina nanoparticles, thermophoresis, stratification of thermal energy, Brownian motion and nonlinear thermal radiation. In addition, the aim and objectives of this paper fill such vacuum in the industry. [ABSTRACT FROM AUTHOR]

In the present article, the problem of boundary layer flow of MHD electrically conducting fluid past a cone and a wedge with non-uniform heat source/sink along with Cattaneo-Christov heat flux is investigated numerically. At first, the flow equations are converted into ODE via appropriate self similarity transforms and the resulting equations are solved with the assistance of R.-K. and Newton’s methods. The influence of several dimensionless parameters on velocity and temperature fields in addition to the friction factor and reduced heat transfer coefficient has been examined with the support of graphs and numerical values. The heat transfer phenomenon in the flow caused by the cone is excessive when compared to the wedge flow. Also, the thermal and momentum boundary layers are not the same for the flow over a cone and wedge. [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]

In this study, we investigated the momentum and heat transfer characteristics of Casson nanofluid flow over a rotating cone in a rotating frame filled with water based CoFe 2 O 4 nano particles. Heat flux conditions and wall temperature conditions are very important in controlling of up and down heat transport phenomena's in industrial as well as engineering application. Resulting set of coupled nonlinear governing equations are solved numerically using Runge–Kutta based shooting technique. In graphical results we presented dual solutions for the prescribed wall temperature (PWT) and prescribed heat flux (PHF) cases. The effect of governing parameters on velocity and temperature fields along with the skin friction coefficient and the heat transfer rate are presented with the help of graphs and tables. Results indicate that the rising values of the volume fraction of ferro particles and buoyancy parameter have tendency to improve the skin friction coefficient as well as the heat transfer rate for both the prescribed wall temperature (PWT) and prescribed heat flux (PHF) cases. [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 knowledge of heat transfer of MHD nanofluid flows over different geometries is very important for heat exchangers design, transpiration, fiber coating, etc. With this initiation, mathematical model is developed to investigate the heat transfer nature of electrically conducting magnetohydrodynamic nanofluid flow over a cone and a wedge. For this investigation, we consider a nonlinear thermal radiation, viscous dissipation, Joule heating with non-uniform heat source/sink effects. Water considered as the base fluid and suspended with copper nanoparticles. R-K and Newton's methods are employed to resolve the altered governing nonlinear equations. Effects of pertinent parameters of concern on the common profiles are conversed (in two cases). It is observed that the momentum and temperature boundary layers are non-uniform for the flow over three a wedge and a cone. Rising the viscous dissipation strengths the velocity and temperature fields. [ABSTRACT FROM AUTHOR]

Nanofluids are potential heat transfer fluids with enhanced thermal and physical properties can be applied in many areas. External magnetic field have tendency to set the thermal and physical properties of nanofluids. With this motivation, we investigated the effects of temperature dependent viscosity, heat source/sink and viscous dissipation on natural convective heat transfer of radiative magnetohydrodynamic (MHD) non-Newtonian nanofluid caused by a cone. For this study, a simulation is performed by mixing of copper nanoparticles in the kerosene. The self similar transformed governing equations are solved by enforcing Runge-Kutta based shooting technique. We acquire the significant accuracy of the recent results by comparing with the published results. In addition, it is indicated that the dual solutions exist for both the base fluid and nanofluid cases. The effects of dimensionless parameters including Eckert number, Weissenberg number, Power-law index, viscous variation parameter, heat source/sink, thermal radiation parameter, and magnetic field parameter on velocity and temperature fields along with the friction factor coefficient and the local Nusselt number are discussed with the help of graphs and tables. It is shown that nanoparticles inclusion into the non-Newtonian fluids has a positive effect on thermal performance. In addition, the viscous variation parameter has a tendency to encourage the friction factor coefficient as well as the heat transfer rate. Moreover, Cu-kerosene nanofluid signifies a better thermal performance than the Ag-kerosene nanofluid. [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]

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]

The current study covers the relative study of non-aligned magnetohydrodynamic stagnation point flow of a nanofluid comprising gyrotactic microorganisms across a stretching sheet in the presence of nonlinear thermal radiation and variable viscosity. The governing equations transitioned as nonlinear ordinary differential equations with suited similarity transformations. With the assistance of Runge-Kutta based shooting method, we derived solutions. Results for oblique and free stream flow cases are exhibited through plots for the parameters of concern. In tabular form, heat and mass transfer rate along with the local density of the motile microorganisms are analyzed for some parameters. It is found that local density of the motile microorganisms is highly influenced by the Biot and Peclet numbers. Rising values of the magnetic field parameter, Biot number, thermal radiation parameter and thermophoresis parameter increase the thermal boundary layer. Bioconvection Peclet number and bioconvection Lewis number have tendency to reduce the density of the motile microorganisms. It is also found that thermal and concentration boundary layers become high in free stream flow when compared with the oblique flow. [ABSTRACT FROM AUTHOR]

The effect of transpiration on magnetohydrodynamic stagnation-point flow of a Carreau nanofluid toward a stretching/shrinking sheet in the presence of thermophoresis and Brownian motion was investigated numerically. The transformed governing partial differential equations are solved using Runge–Kutta coupled with shooting technique. The effect of pertinent parameters on velocity, temperature and concentration profiles along with the friction factor, local Nusselt and Sherwood numbers is presented graphically and through tables. It is observed that, increasing values of the thermophoresis parameter enhances the heat and mass transfer rate, whereas the Weissenberg number enlarges the momentum boundary layer thickness along with the heat and mass transfer rate. A good agreement of the present results has been observed by comparing with the published results. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the effects of aligned magnetic field, thermal radiation, heat generation/absorption, cross-diffusion, viscous dissipation, heat source and chemical reaction on the flow of a nanofluid past an exponentially stretching sheet in porous medium. The governing partial differential equations are transformed to set of ordinary differential equations using self-similarity transformation, which are then solved numerically using bvp4c Matlab package. Finally the effects of various non-dimensional parameters on velocity, temperature, concentration, skin friction, local Nusselt and Sherwood numbers are thoroughly investigated and presented through graphs and tables. We observed that an increase in the aligned angle strengthens the applied magnetic field and decreases the velocity profiles of the flow. Soret and Dufour numbers are helpful to enhance the heat transfer rate. An increase in the heat source parameter, radiation parameter and Eckert number increases the mass transfer rate. Mixed convection parameter has tendency to enhance the friction factor along with the heat and mass transfer rate. [ABSTRACT FROM AUTHOR]

In this study we analyzed the momentum and heat transfer behavior of CuO-water and Al2O3-waternanofluids embedded with micrometer sized conducting dust particles towards a porous stretching/shrinking cylinder at different temperatures in presence of suction/injection, uniform magnetic field, shape of nano particles, volume fraction of micro and nano particles. The governing boundary layer equations are transformed to nonlinear ordinary differential equations by using similarity transformation. Numerical solutions of these equations can be obtained by using Runge-Kutta Felhberg technique. The influence of non-dimensional governing parameters on the flow field and heat transfer characteristics are discussed and presented through graphs and tables. Results indicates that spherical shaped nano particles showed better thermal enhancement compared with cylindrical shaped nano particles, increase in volume fraction of nano particles helps to enhance the uniform thermal conductivity. But it does not happen by increase in volume fraction of dust particles. Enhancement in fluid particle interaction reduces the friction factor and improves the heat transfer rate. [ABSTRACT FROM AUTHOR]

In this study we investigated the effect of space and temperature dependent heat generation/absorption on three-dimensional magnetohydrodynamic nanofluid flow over a nonlinearly permeable stretching sheet. After using appropriate self-similarity transformation the governing equations are solved numerically using bvp4c Matlab package. The effects of the non-dimensional governing parameters on velocity, temperature and concentration profiles are discussed with the help of graphs. Also, coefficient of skin friction and Nusselt number is analyzed and presented through tables. It is found that present results have an excellent agreement with the existed studies under some special cases. Results indicate that an increase in space and temperature dependent heat source or sink increases the temperature and concentration profiles of the flow. Dual solutions exist only for certain range of power-law index. [ABSTRACT FROM AUTHOR]

In this study we analyzed the flow, heat and mass transfer behavior of Jeffrey, Maxwell and Oldroyd-B nanofluids over a permeable stretching sheet in the presence of transverse magneticfield, thermophoresis, Brownian motion and suction/injection. The governing partial differential equations are transformed into system of nonlinear ordinary differential equations by using self similarity transformation and solved numerically by using Runge–Kutta based shooting technique. The effects of non-dimensional governing parameters on the flow, heat and mass transfer are discussed with the help of graphs. Also the skin the friction coefficient, local Nusselt and Sherwood numbers are presented through graphs. We found that the results in this study prove to be highly satisfactory with the existing results. We observed that the heat and mass transfer rate in Oldroyd-B nanofluid is significantly high compared with the Jeffery and Maxwell nanofluids. It is also observed that the friction factor of Maxwell nanofluid is less compared with the Oldroyd-B and Jeffrey nanofluid. [ABSTRACT FROM AUTHOR]

In this study we analyze the boundary layer flow of a thermophoretic magnetohydrodynamic dissipative nanofluid over an unsteady stretching sheet in a porous medium with space and time dependent internal heat source/sink. The governing equations are transformed to ordinary differential equations by using similarity transformation. Numerical solutions of these equations are obtained by using the Shooting Technique. The effects of non-dimensional governing parameters on the velocity, temperature, concentration profiles, friction factor, Nusselt and Sherwood numbers are discussed and presented through graphs and tables. Accuracy of the results compared with the existing ones. Excellent agreement is found with earlier studies. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze the influence of wall flexibility and Joule heating on the peristaltic transport of a conducting nanofluid in uniform/non-uniform porous channel. The exact solutions are obtained for stream function and velocity. Further, R-K-Fehlberg integration scheme is applied to solve the energy and concentration equations. Results obtained and discussed for the flow over uniform and non-uniform geometries at different values of relevant parameters. Moreover, the trapping phenomena are investigated with the help of streamlines. Non-uniform geometry parameter, magnetic parameter, and permeability parameter have a strong impact on trapping phenomena. The fluid velocity is high in the diverging channel when compared to the uniform channel, while the situation is reversed for temperature and concentration fields. [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]

In this paper, we examined the significance of nonlinear thermal radiation on 2-D magnetohydrodynamic flow of hybrid nanoliquid across two distinct geometries. The hybridized nanoliquid is encompassed with CuO and Al 2 O 3 nanomaterials suspended in the base liquid (water). The suitable similarity transmutations are utilized to convert the PDE's to the non-dimensional ODE's and solved them by employing Runge-Kutta method with shooting procedure. Further, simultaneous solutions are witnessed for flow over cone case and plate case respectively. The stimulus of dimensionless parameters on velocity and thermal fields are discussed thru plots, further, the wall friction and local Nusselt number are presented thru the tables. The results reveal that, the nonlinear thermal radiation has a propensity to boosts the thermal distributions and to decays the rate of heat transfer. The flow and thermal distributions are significant in flow over a plate as compared with flow over a cone case. Moreover, the thermal transport rate of the flow above a cone is considerably advanced than that of flow over a plate. [ABSTRACT FROM AUTHOR]