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A mathematical model is used to discuss a comparative study of AA7072 (nanofluid) and AA7072/AA7075 (hybrid nanofluid) flow through endoscope. For this evaluation, AA7072 (which is the combination of Al (98 %) and Zn (1 %) mixed with metals Si, Fe and Cu) and AA7075 (which is the mixture of Al (90 %) , Zn (6 %) , Mg (3 %) and Cu (1 %) mixed with metals Si, Fe and Mg) are considered as nanoparticles and water as a base fluid. The inner cylinder is endoscope (rigid and fixed) moving with constant velocity (V) , while the external cylinder is sinusoidal (wave moving down to its boundaries) like the shape of artery in the form of concentration and relaxation phenomena. Low Reynolds number and long wavelength estimation is applied for analytic solution. The resulting nonlinear PDEs are transformed into ODEs by perturbation technique. After this, we compare graphically the behavior of nanofluid and hybrid nanofluids for velocity profile, temperature profile, friction forces on inner and outer cylinders, pressure gradient and pressure rise for different values of solid volume fractions and inner cylinder radius. [ABSTRACT FROM AUTHOR]

The flow of 2-D cross fluid model with mass and heat transmission over a linearly stretched sheet is analyzed in this paper. Furthermore, we have expanded our study by considering the effects of MHD flow, stagnation point, double stratification, heat generation, radiation effect, nanofluid flow, activation energy and mass diffusion. This type of study has not being investigated previously in literature. The flow generating PDEs are altered into ODEs by deploying suitable transformations. The effects of the parameters involved, namely the Weissenberg number, magnetic field coefficient, Brownian motion coefficient, radiation parameter, Damkohler number, thermophoresis coefficient, Schmidt number, activation energy, heat generation parameter and temperature difference coefficient on the velocity, concentration and energy fields are thoroughly scrutinized. The problem is solved through numerical technique (BVP4c) on MATLAB. The outcomes reveal that the velocity curve upsurges for rising Weissenberg number and decreases due to magnetic parameter. The heat field improves for increasing behavior of the Brownian motion, thermophoresis, heat generation, thermal conductivity and radiation coefficient whereas reverse results are obtained due to Prandtl number and stratification parameter. The concentration improves due to thermophoresis parameter and diffusivity coefficient while reverse outcomes are noticed due to Schmidt number, Damkohler number, temperature difference parameter and Brownian motion parameter. [ABSTRACT FROM AUTHOR]

This study deals with the investigation of boundary layer nanofluid flow on a slender paraboloid surface. The front tip of bullet, airplane, missiles and rockets are some examples of this surface. The thermal conductivity and viscosity of fluid has importance in many engineering applications such as auto mobile industries, solar power generation and heat exchangers, therefore the fluid property such as viscosity is considered to be temperature dependent. The thermophoretic motion, Brownian motion, heat generation and chemical reaction effects examines the behavior of heat and mass transport. The unsteady governing model includes momentum, heat and concentration equations which occur in the form of coupled PDEs. In order to solve numerically, a set of suitable transformations simplify the basic governing laws and convert these equations in the form of coupled ODEs. To show the graphical behavior, we simplify determine model of equations by using Matlab software via BVP4c method a built in command. At last, the discussion related to graphs for variation in different parameters are included. [ABSTRACT FROM AUTHOR]

When an object moves alongside a curved surface, it shows a curvilinear motion. The perception of curvilinear motion is majorly used in applications which are associated with centripetal and centrifugal forces. In this analysis, we studied the behaviour of nano-fluid and hybrid nano-fluid via curved surface with combined effects of heat generation and porous medium. For nano-fluid the combination of base fluid methanol and nano-particles AA7075 are assumed, while for hybrid nano-fluid base fluid methanol and nano-particles AA7075+AA7072 are used. AA7072 is mixture of zinc and alumina with some metals like copper, silicon and ferrous. Similarly AA7075 is mixture of magnesium, alumina and zinc with metals copper, silicon and ferrous. The partial differential equations are converted into ordinary differential equations by using similarity transformation. With the help of MATLAB software we used Bvp4c method to draw the graphs of the resulting equations and also we discuss the effect of solid volume fraction φ 1 , φ 2 , curvature parameter λ , Heat generation ω and porous medium ε for nano-fluid and hybrid nano-fluid. By enhancing the curvature parameter and volume fraction the temperature and velocity profile also enhances while the velocity profile reduces for porous medium and temperature profile increases for heat generation parameter. Nusselt number and skin friction effects are studied in the form of tables. An entropy generation analysis is also conducted. [ABSTRACT FROM AUTHOR]

In present analysis, we investigate the flow behavior of SiO 2 / H 2 O / C 2 H 6 O 2 nanofluid along with magnetic field and heat generation influence on permeable channel having squeezing/dilating walls. The modeled partial differential system including mass balance, momentum and temperature equations are transformed into ordinary differential system by using similarity transformations and achieved the coupled of nonlinear ordinary differential equations. The numerical solution of coupled system of equations is interpreted for velocity and temperature by using Bvp4c method. The graphical behavior of different parameters such as deforming rate L (for velocity we have taken L = ± 0. 1 , ± 0. 7 and ± 1. 2 , wheres for temperature L = − 0. 1 , − 0. 7 and − 0. 9 has been taken), permeating Reynolds number H (for velocity H = 0. 1 , 0. 4 and 0.7 and for temperature H = − 0. 6 , − 0. 7 and − 0. 8 has been taken), Hartman number M (for velocity M = 0. 1 , 1. 3 and 2.5 is taken), heat generation β (for temperature β = 0. 1 , 0. 5 and 0.9 is taken) and solid fraction volume R (for velocity R = 0. 1 , 0. 9 and 1.2 is taken, for temperature R = 0. 7 , 0. 8 and 0.9 is assumed) for temperature and velocity have been plotted using Matlab software. The observation of case I; L > 0 , H > 0 , shows the velocity of both base ( H 2 O and C 2 H 6 O 2 ) fluids increases at middle portion of channel due to increase in L and M. On the other hands the velocity profiles show increasing behavior for H and decreasing behavior for R at the edges of channel. Temperature distribution observation of case I; L > 0 , H > 0 , it is cleared that the temperature of SiO 2 / H 2 O / C 2 H 6 O 2 nanofluid increases due to increase of β. The temperature profile of SiO 2 / H 2 O nanofluid decreases by increase of R, on other hands the temperature profile of SiO 2 / C 2 H 6 O 2 nanofluid decreases on interval (− 1 < h < 0) and increases on interval (0 < h < 1) with increase of R. The observation of case II; L < 0 , H < 0 , deduces that the temperature of SiO 2 / H 2 O / C 2 H 6 O 2 nanofluid increases by increase of H. The graphical results show that temperature profile reveals batter performance for base fluid H 2 O as compared to base fluid C 2 H 6 O 2 . We compared the present results with previous results and found that present results are similar to previous results. • SiO 2 / H 2 O / C 2 H 6 O 2 nanofluid in squeezing/dilating wall are investigated. • Heat generation is considered. • Low Reynolds number and long wavelength approximation is used. • The equations are solved by using perturbation technique. • Relationship between kinematic viscosity and intermolecular forces are described. [ABSTRACT FROM AUTHOR]

• The boundary-flows over a parabolic surface is computed for viscous fluid. • For large Reynolds number the basic flow may be determined numerically in terms of a similarity variable. • Resulting in enhanced heat transfer properties of the fluid. • Relationship between kinematic viscosity and intermolecular force is described. This article presents a study of nanofluid and hybrid nanofluid near a parabolic surface under the influence of heat generation and MHD. AA7072 and AA7075 are treated as nano particles while mathanol is used as a base fluid. We incorporated aluminum alloy of AA7072 in a base fluid for nanofluid and AA7072+AA7075 in base fluid for hybrid nanofluid. AA7072 and AA7075 manipulated in this study are uniquely manufactured to possess high heat transfer features. AA7072 alloy is a combined mixture of zinc and aluminium with some metallic elements such as copper, silicon, and ferrous. Similarly AA7075 is a compounded mixture of zinc, magnesium, ferrous, and silicon. By using similarity transformations, the PDEs are transmuted into ODEs. Furthermore, the transmuted equations are than interpreted numerically in MATLAB using Bvp4c. The graphical analysis is performed for different parameters to check the behaviour of velocity and temperature profiles. Velocity field attains increasing behaviour by an accretion in volume fraction ϕ 1 for both methanol+AA7072(nanofluid) and methanol+AA7072+AA7075(hybrid nanofluid). The velocity profile for methanol+AA7072 is higher than methanol+AA7072+AA7075. By increasing magnetic field parameter M, the velocity component f ′ (ψ) proceeds diminish trend for both methanol+AA7072 and methanol+AA7072+AA7075. But velocity field for methanol+AA7072 is moderate than methanol+AA7072+AA7075. The influence of heat generation parameter γ shows rising trend in temperature profile for both fluids. But heat generation parameter γ is more effective for hybrid nanofluid. Moreover, an entropy generation rate is also evaluated. [ABSTRACT FROM AUTHOR]