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The current paper aims to analyse the magnetic behaviour on squeezing flow of hybrid-nanofluid. Additionally, features of activation energy and chemical reaction are introduced. Aluminium oxide (Al2O3) and copper (Cu) are taken as nanoparticles in hybrid-nanofluids. The flow model is taken with no-slip conditions. To convert the leading PDEs to ODEs we use apposite similarity transformations and solve numerically utilizing the RK technique with the abetment of the shooting method. The upshot of some parameters on the flow system is accomplished precisely through figures and charts. Significances of variable parameters on skin friction, Nusselt number and Sherwood number are mathematically deliberated. The consequence approves that the rate of mass transmission is in a linear association with activation energy, and it discloses a reverse linking with the chemical reaction parameter. The outcomes confirm that amount of heat transport is improved in presence of magnetic field due to the squeezing flow.

Nanofluid has a wide range of uses in various fluid systems, because of its excellent growth in thermal conductivity. The current paper explores the transfer of heat and mass process in MHD nanofluid flow across a stretching sheet, considering the collective impacts of nonlinear thermal radiation, Joule heating, and binary chemical reactions with convective boundary conditions for Williamson nanofluid. The necessary transformations are carried out to alter the controlling PDE’s into a collection of linked ODE’s. The shooting approach, in conjunction with the fourth-order Runge–Kutta method, is employed to get solutions to highly nonlinear ODE’s. The impact of varied main factors on velocity, temperature, concentration, for Weissenberg number, Biot number along with other parameters are depicted graphically, whilst the change in the rate of heat and mass transfer is investigated via numerical data in tabular form. The acquired numerical data show that expanding the Eckert number diminishes the rate of mass transfer whereas expanding the thermal radiation parameter, expandsthe rate of heatand rate of mass transfer.

This work presents a numerical and an analytical review of analysis of the convective phenomenon in a non-Newtonian nanofluid layer with the applied vertical magnetic field and having an internal heating source. Buongiorno model is used to examine the convective instability considering the impacts of thermophoresis, Brownian diffusion, and viscoelasticity of the nanofluid. The effect of significant parameters concerning stability is visualized through graphs and further interpreted. For the non-linear study, the fundamental PDEs are converted into non-linear simultaneous autonomous ODEs. The solutions are computed by taking the help of the software Mathematica. Nusselt number and Sherwood number are graphed for numerous parametric situations to offer a clear outlook of heat and mass transfer rate. The magnetic field parameter stabilizes the system and diminishes heat and mass transfer. Elevating the internal heat parameter promotes heat and mass transfer significantly. Viscoelasticity of the fluid affects prominently since non-Newtonian fluid yields lower heat and mass transfer coefficients than Newtonian fluid due to advancement of the convection.

The current research examines the characteristic of dissipative heat energy owing to the inclusion of a magnetic field here on the two-dimensional flow of an electrically conducting hybrid nanofluid past an expanding surface. Additionally, the free convection of hybrid nanofluid thermal properties is enhanced with the inclusion of the Joule heating effect as well as the thermal radiation in the heat transfer phenomenon. These physical properties were influenced as a result of the combination of the nanoparticles Al2O3 and Cu into the base liquid ethylene glycol. The novelty arises due to the interaction of thermal conductivity employing the Mintsa model and the viscosity using the Gharesim model. The transformed governing set of nonlinear equations obtained with the assistance of suitable similarity transformations are solved numerically using the Runge-Kutta fourth-order shooting base technique. A good correlation between the earlier studies is obtained in specific cases showing the convergence criteria of the present procedure. Further, the physical significance of the contributive parameters is presented through graphs and tables. The observation shows that the particle concentration for the hybrid nanofluid augments the fluid velocity. Moreover, the inclusion of dissipative heat favors enhancing the fluid temperature for the involvement of the particle concentration.

A plain linear penetrable contracting sheet with slip over a micro-polar liquid with a stagnation-point flow is analyzed. Through similarity mapping, the mathematical modeling statements are transformed as ODE’s and numerical results are found by shooting techniques. The varying impacts of physical quantities on the momentum, micro-rotation, and temperature were demonstrated through graphs. The computed measures including shear and couple stress with distinct measures of factors involved in this proposed problem are presented through a table.

The current study investigates the intrinsic irreversibility phenomenon of a mixed convection and electrically conducting couple stress Casson fluid motion over a thermally stretching sheet. We have considered the combined effect of applied magnetic field, Brownian motion, thermal radiation, permeability, Casson parameter, and the stretching parameter on the entropy generation rate of the model. The first and second laws of thermodynamics have been applied to examine the flow problem. The obtained dimensionless structure of highly nonlinear ordinary differential equations is then solved numerically applying the overlapping grid spectral collocation method. This method has high accuracy and converges fast. The approximate solutions for velocity, temperature and concentration are used to evaluate the rate of entropy generation and some physical parameters of the flow. For engineering interest, we have obtained tabular results for the skin friction coefficient, Nusselt number, and the Sherwood number for pertinent parameters. We found that entropy generation rate is minimized when there is an increase in the applied magnetic field, thermophoresis parameter, Casson parameter, Brownian motion, and the energy variance parameter. Further, the entropy generation rate is increased by enhancing the stretching parameter, permeability parameter, the Biot number, and thermal radiation parameter.

Present paper aims to analyze three-dimensional (3D) motion of an electrically conducting nanofluid past an exponentially stretching sheet. Both metal and metal oxide nanoparticles (such as Cu, Al2O3, TiO2) in the base fluid (water) are examined. Nonlinear ordinary differential systems are obtained by suitable transformations. The crux of the analysis is the development of an estimated analytical result obtained by employing the “Adomian Decomposition Method” (ADM), an approximate analytical method. Momentum and energy descriptions with prescribed boundary conditions are employed. The velocity components and temperature are analyzed. Tabulated values are organized aimed at the outcomes of skin-friction coefficients and Nusselt number. Comparison with past limiting results is shown. Finally, the outstanding outcomes of the present result are; the velocity profile with the inclusion of particle concentration and magnetic parameter decelerate significantly and Al2O3 nanoparticles are favorable for the enhancement in the rate of heat transfer.

This paper deals with nanofluid flow between parallel plates and heat transfer through porous media with heat source /sink. The governing equations are transformed into self-similar ordinary differential equations by adopting similarity transformations and then the converted equations are solved numerically by Runge-Kutta fourth order method. Special emphasis has been given to the parameters of physical interest which include Prandtl number, magnetic parameter, porous matrix, chemical reaction parameter and heat source parameter. The results obtained for velocity, temperature and concentration are shown in graphs. The comparison of the special case of this present results with the existing numerical solutions in the literature shows excellent agreement.

A free convection viscous MHD flow over a semi-infinite vertical sheet with convective heat and mass conditions has been considered. The effects of thermal radiation, chemical reaction and Joule heating on flow are also accounted. The governing nonlinear partial differential equations have been transformed into a set of highly non-linear coupled ordinary differential equations (ODEs) using appropriate similarity transformations. Numerical solutions of transformed equations are obtained by employing the 5th order Runge-Kutta Fehlberg technique followed by the shooting technique. The influences of different flow parameters on the momentum, energy and mass field are discussed and shown graphically. Results reveal that temperature and concentration profiles enhance due to increasing heat and mass Biot number parameters.

This work deals with the numerical solutions of combustible boundary layer flow over an axisymmetric body. A mathematical structure is taken out by explaining the governing equations of continuity, velocity, energy and concentration. These are solved employing the finite difference technique. The nature of the flow is analyzed using velocity, temperature and mass concentration for different physical parameters such as, surface location, Prandtl number, Schmidt number, viscosity variation parameter, thermal conductivity parameter and the radiation parameter. It is found that the viscosity variation and thermal conductivity parameter augment the thicknesses of thermal and concentration layers and reduces the momentum thickness. Moreover, the momentum, thermal and concentration boundary layers become thick for larger values of radiation parameter whereas the reverse characteristic is observed for higher value of the Prandtl number.

An investigation has been carried out for the MHD 3-dimensional flow of nanofluid over a shrinking sheet saturating a porous media in the presence of thermal radiation and heat generation. Convective boundary conditions for the flow phenomena are used in the present analysis. The governing equations are reduced to ODEs employing suitable similarity transformations. The solutions of formulated differential equations have been attained mathematically by fourth order R-K technique along with the shooting method. The impact of the governing constraints on momentum, heat, and local Nusselt number, are explored. It is noticed that the momentum and heat decrease with raise in the porosity variable, temperature reduces with an enhance in the thermal radiation variable, and temperature enhances with an enhance in the heat source/sink parameter.

Fingerprint recognition techniques are immensely dependent on quality of the fingerprint images. To improve the performance of recognition algorithm for poor quality images an efficient enhancement algorithm should be designed. Performance improvement of recognition algorithm will be more if enhancement process is adaptive to the fingerprint quality (wet, dry or normal). In this paper, a quality adaptive fingerprint enhancement algorithm is proposed. The proposed fingerprint quality assessment algorithm clusters the fingerprint images in appropriate quality class of dry, wet, normal dry, normal wet and good quality using fuzzy c-means technique. It considers seven features namely, mean, moisture, variance, uniformity, contrast, ridge valley area uniformity and ridge valley uniformity into account for clustering the fingerprint images in appropriate quality class. Fingerprint images of each quality class undergo through a two-stage fingerprint quality enhancement process. A quality adaptive preprocessing method is used as front-end before enhancing the fingerprint images with Gabor, short term Fourier transform and oriented diffusion filtering based enhancement techniques. Experimental results show improvement in the verification results for FVC2004 datasets. Significant improvement in equal error rate is observed while using quality adaptive preprocessing based approaches in comparison to the current state-of-the-art enhancement techniques., Comment: 34 pages, 8 figures, Submitted to Image and Vision Computing

Fingerprint-based recognition has been widely deployed in various applications. However, current recognition systems are vulnerable to spoofing attacks which make use of an artificial replica of a fingerprint to deceive the sensors. In such scenarios, fingerprint liveness detection ensures the actual presence of a real legitimate fingerprint in contrast to a fake self-manufactured synthetic sample. In this paper, we propose a static software-based approach using quality features to detect the liveness in a fingerprint. We have extracted features from a single fingerprint image to overcome the issues faced in dynamic software-based approaches which require longer computational time and user cooperation. The proposed system extracts 8 sensor independent quality features on a local level containing minute details of the ridge-valley structure of real and fake fingerprints. These local quality features constitutes a 13-dimensional feature vector. The system is tested on a publically available dataset of LivDet 2009 competition. The experimental results exhibit supremacy of the proposed method over current state-of-the-art approaches providing least average classification error of 5.3% for LivDet 2009. Additionally, effectiveness of the best performing features over LivDet 2009 is evaluated on the latest LivDet 2015 dataset which contain fingerprints fabricated using unknown spoof materials. An average classification error rate of 4.22% is achieved in comparison with 4.49% obtained by the LivDet 2015 winner. Further, the proposed system utilizes a single fingerprint image, which results in faster implications and makes it more user-friendly., Comment: 21 pages, 11 figures, 7 Tables

Investigation of an MHD convective flow of viscous, incompressible and electrically conducting fluid through a porous medium bounded by two infinite vertical parallel porous plates is carried out. Forchheimer-Brinkman extended Darcy model is assumed to simulate momentum transfer within the porous medium. A magnetic field of uniform strength is applied normal to the plates. The analytical results are evaluated numerically and the presented graphically to discuss in detail the effects of different parameter entering into the problem.

An analysis is presented to investigate the effects of thermal radiation on a convective slip flow of an electrically conducting slightly rarefied fluid, having temperature dependent fluid properties, over a wedge with a thermal jump at the surface of the boundary in the presence of a transverse magnetic field. The reduced equations are solved numerically using the finite difference code that implements the 3-stage Lobatto IIIa formula for the partitioned Runge-Kutta method. Numerical results for the dimensionless velocity and temperature as well as for the skin friction coefficient and the Nusselt number are presented through graphs and tables for pertinent parameters to show interesting aspects of the solution.

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.

This paper discusses the effect of heat and mass flux on the natural convective laminar flow of a viscous incompressible fluid under the influence of radiation, magnetic field and Joule heating. The partial differential equations related to the problem have been changed as a set of ordinary differential equations employing non-dimensional quantities. Semianalytical approach such as the Adomian decomposition method (ADM) is employed to solve the system of ordinary differential equations. The behaviour of characterising parameters on the velocity, heat and mass transfer profiles, and the engineering quantities of interest, i.e. skin friction, heat and mass transfer rates and other indices are presented through graphs.

The present work is concerned with heat and mass transfer of an electrically conducting second grade MHD fluid past a semi-infinite stretching sheet with convective surface heat flux. The analysis accounts for thermophoresis and thermal radiation. A similarity transformations is used to reduce the governing equations into a dimensionless form. The local similarity equations are derived and solved using Nachtsheim-Swigert shooting iteration technique together with Runge–Kutta sixth order integration scheme. Results for various flow characteristics are presented through graphs and tables delineating the effect of various parameters characterizing the flow. Our analysis explores that the rate of heat transfer enhances with increasing the values of the surface convection parameter. Also the fluid velocity and temperature in the boundary layer region rise significantly for increasing the values of thermal radiation parameter.Highlights Effect of thermal radiation on second grade fluid in the presence of thermophoresis is studied. The rate of mass transfer increases with the increase of thermophoretic parameter. The rate of heat transfer increases for increasing the values of the surface convection parameter. The temperature profile enhances with increase in the thermal radiation parameter.

The aim of the present work is to propose a user friendly approach based on homotopy analysis method combined with Sumudu transform method to drive analytical and numerical solutions of the fractional Newell-Whitehead-Segel amplitude equation which describes the appearance of the stripe patterns in 2-dimensional systems. The coupling of homotopy analysis method with Sumudu transform algorithm makes the calculation very easy. The proposed technique gives an analytic solution in the form of series which converge very fastly. The analytical and numerical results reveal that the coupling of homotopy analysis technique with Sumudu transform algorithm is very easy to apply and highly accuratewhen apply to non-linear differential equation of fractional order.

A theoretical study is carried out to obtain an analytical solution of free convective heat transfer for the flow of a polar fluid through a porous medium with variable permeability bounded by a semi-infinite vertical plate in a slip flow regime. A uniform magnetic field acts perpendicular to the porous surface. The free stream velocity follows an exponentially decreasing small perturbation law. Using the approximate method the expressions for the velocity, microrotation, and temperature are obtained. Further, the results of the skin friction coefficient, the couple stress coefficient and the rate of heat transfer at the wall are presented with various values of fluid properties and flow conditions.