Band 8, Heft 1

In the this paper, a new modified method is proposed for solving linear and nonlinear Lane-Emden type equations using first kind Chebyshev operational matrix of differentiation. The properties of first kind Chebyshev polynomial and their shifted polynomial are first presented. These properties together with the operation matrix of differentiation of first kind Chebyshev polynomial are utilized to obtain numerical solutions of a class of linear and nonlinear LaneEmden type singular initial value problems (IVPs). The absolute error of this method is graphically presented. The proposed framework is different from other numerical methods and can be used in differential equations of the same type. Several examples are illuminated to reveal the accuracy and validity of the proposed method.

The paper examines design and operating data of current concentrated solar power (CSP) solar tower (ST) plants. The study includes CSP with or without boost by combustion of natural gas (NG), and with or without thermal energy storage (TES). Latest, actual specific costs per installed capacity are high, 6,085 $/kW for Ivanpah Solar Electric Generating System (ISEGS) with no TES, and 9,227 $/kW for Crescent Dunes with TES. Actual production of electricity is low and less than the expected. Actual capacity factors are 22% for ISEGS, despite combustion of a significant amount of NG exceeding the planned values, and 13% for Crescent Dunes. The design values were 33% and 52%. The study then reviews the proposed technology updates to improve ratio of solar field power to electric power, capacity factor, matching of production and demand, plant’s cost, reliability and life span of plant’s components. Key areas of progress are found in materials and manufacturing processes, design of solar field and receiver, receiver and power block fluids, power cycle parameters, optimal management of daily and seasonal operation of the plant, new TES concepts, integration of solar plant with thermal desalination or combined cycle gas turbine (CCGT) installations and specialization of project.

The separately excited Direct Current (DC) motor is widely used in many industrial sectors. During the operation of the DC motor, the load torque and the voltage of the network can cause a destabilization of the actual speed and actual current. Thus, the need to regulate the speed and current of the DC motor is a very important research problem. In this paper, a control strategy of separately excited DC motor using a series multi-cells chopper is described. The proposed control is based on Proportional-Integral (PI) and Petri nets controllers. Specifically, the conventional PI controller is used to control the speed of DC motor. The Petri nets controller ensures the regulation of the armature current and to maintain the capacitor voltage of the multi-cells converter to its reference. The Petri nets controller also generates binary control switches. The proposed control system has been implemented using MATLAB Sim Power. Simulation results demonstrate that a series multi-cells chopper and the proposed control give a good performance and high robustness in load disturbance for the separately excited DC motor.

The boundary roughness effects on nonlinear saturation of Rayleigh-Taylor instability (RTI) in couple-stress fluid have been studied using numerical technique on the basis of stability of interface between two fluids of the system. The resulting fourth order ordinary nonlinear differential equation is solved using Adams-Bashforth predictor and Adams-Moulton corrector techniques numerically. The various surface roughness effects and surface tension effects on nonlinear saturation of RTI of two superposed couple-stress fluid and fluid saturated porous media are well investigated. At the interface, the surface tension acts and finally stability of the problem is discussed in detail.

In this paper, the counter – current imbibition phenomena in a heterogeneous porous media is studied with the consideration of two types of porous materials like volcanic and fine sand and Adomian decomposition method is applied to find the saturation of wetting phase and the recovery rate of the reservoir. A simulation result is developed here to study the effect of heterogeneity, capillarity and relative permeability on saturation rate and to obtain an optimum recovery rate of the reservoir with the choices of some interesting parametric value.

The electro-osmotic flow of a third grade fluid past a channel having stretching walls has been studied in this paper. The channel height is taken much greater than the thickness of the electric double layer comprising of the Stern and diffuse layers. The equations governing the flow are obtained from continuity equation, the Cauchy’s momentum equation and the Poisson-Boltzmann equation. The Debye-Hückel approximation is adopted to linearize the Poisson-Boltzmann equation. Suitable similarity transformations are used to reduce the resulting non-linear partial differential equation to ordinary differential equation. The reduced equation is solved numerically using damped Newton’s method. The results computed are presented in form of graphs.

The present study examines the effect of heat transfer on electrically conducting MHD micropolar fluid flow along a semi-infinite horizontal plate with radiation and heat source. The uniform magnetic field has applied along the principal flow direction. The obtained governing equations have been converted into a set of dimensionless differential equations and then numerically solved by using a well-known Runge-Kutta method with shooting technique. The velocity, microrotation, and temperature distribution are presented for various physical parameters. The numerical values of skin friction and Nusselt numbers at the plates are shown in tabular form, and the obtained results are compared with the results of a previous study. It has been found that the magnetic parameter increases the velocity profile whereas the boundary layer thickness reduces due to the inclusion of coupling parameter and inertia effect. The presence/absence of magnetic parameter and coupling parameter enable to enhance the angular velocity profile while it is worth to note that the backflow has generated in the vicinity of the plate.

The aim of this study is to extend the applicability of an eighth convergence order method from the k −dimensional Euclidean space to a Banach space setting. We use hypotheses only on the first derivative to show the local convergence of the method. Earlier studies use hypotheses up to the eighth derivative although only the first derivative and a divided difference of order one appear in the method. Moreover, we provide computable error bounds based on Lipschitz-type functions.

In this paper the boundary layer flow of a micro-polar fluid due to a linearly stretching sheet which is a non-linear system two-point boundary value problem (BVP) on semi-infinite interval has been considered. This the sheets are included the suction and injection. We solve this problem by two different collecation approaches and compare their results with solution of other methods. The proposed approaches are equipped by the direct (DRBF) and indirect radial basis functions (IRBF). Direct approach (DRBF) is based on a differential process and indirect approach (IRBF) is based on an integration process. These methods reduce solution of the problem to solution of a system of algebraic equations. Numerical results and residual norm show that the IRBF performs better than the common DRBF, and has an acceptable accuracy and high rate of convergence of IRBF process.

In the present investigation, a problem of natural convective flow of a non-Newtonian power-law fluid over an inclined plate saturated in a non-Darcy porous medium is considered. Also, the nonlinear Boussinesq approximation and convective thermal boundary condition are taken into account to address heat and mass transfer phenomena of thermal systems which are operated at moderate and very high temperatures. The steady-state boundary layer equations are non-dimensionalized into non-similar form and then solved numerically by the local non-similarity method with successive linearisation method (SLM). The effects of various physical parameters on the fluid flow, heat and mass transfer characteristics are depicted graphically and analysed in detail.

Empirical investigations of solute fate and carrying in streams and rivers often contain inventive liberate of solutes at an upstream perimeter for a finite interval of time. An analysis of various worth references on surface-water-grade mathematical formulation reveals that the logical solution to the continual-parameter advection- dispersion problem for this type of boundary state has been generally missed. In this work, we study the q -fractional homotopy analysis transform method ( q -FHATM) to find the analytical and approximate solutions of space-time arbitrary order advection-dispersion equations with nonlocal effects. The diagrammatical representation is done by using Maple package, which enhance the discretion and stability of family of q -FHATM series solutions of fractional advection-dispersion equations. The efficiency of the applied technique is demonstrated by using three numerical examples of space- and time-fractional advection-dispersion equations.

Mass transfer around a slender drop in a nonlinear extensional and creeping flow is theoretically studied. The fluid mechanics problem is governed by three dimensionless parameters: The capillary number ( Ca ≫ 1), the viscosity ratio ( λ ≪ 1), and the nonlinear intensity of the flow (| E | ≪ 1). The transfer of mass around such a drop is studied for the two asymptotic cases of large and zero Peclet numbers ( Pe ). The results show that as the capillary number increases, the drop becomes longer, thinner, its surface area increases, leading to larger mass transfer rates, especially at large Peclet numbers, since then convection contributes to the overall mass transfer as well. Taking a slender inviscid drop ( λ = 0) in a linear extensional flow ( E = 0) as our reference case, we find that the addition of nonlinear effects to the flow sometimes increases ( Eλ −1 Ca −2 < 64/9) and sometimes decreases ( Eλ −1 Ca −2 > 64/9) the rate of mass transfer.

In this article, the study of heat, momentum and mass (species) transfer in an electro-conductive polymer on the external surface of a vertical plate. The effects of Brownian motion and thermophoresis are incorporated in the model in the presence of both heat and nanoparticle mass transfer convective conditions. The Williamson viscoelastic model is employed which is representative of certain industrial polymers. The non-dimensional, transformed boundary layer equations for momentum and energy are solved with the second order accurate implicit Keller box finite difference method under appropriate boundary conditions. The influence of Weissenberg number, magnetic body force parameter, thermal slip parameter, hydrodynamic slip parameter, stream wise variable and Prandtl number on thermo fluid characteristics are presented graphically and discussed. A weak elevation in temperature accompanies increasing Weissenberg number whereas a significant acceleration in the flow is computed near the plate surface. Rate of heat transfer is reduced with increases the Weissenberg number. The study is relevant to enrobing processes for electric-conductive nano-materials, of potential use in aerospace, smart coating transport phenomena and other industries.

In this paper, the temperature distribution in a convective radial fins is analyzed through a fractional order energy balance equation with the consideration of internal heat generation and temperature dependent thermal conductivity. Adomian decomposition Sumudu transform method is used to study the influence of temperature distribution and the efficiency of radial fins for different values of thermal conductivity and to determine the role of thermal conductivity, thermo-geometric fin parameter as well as fractional order values in finding the temperature distribution and the fin efficiency of the convective radial fins. Finally, the efficiency of this proposed method has been studied by comparing the obtained results with the classical order results obtained by using numerical method and Variational Iteration Method (Coskun and Atay, 2007).

The current work deals with the fractional forms of EW and modified EW equations in the conformable sense and their exact solutions. In this respect, by utilizing a traveling wave transformation, the governing space-time fractional models are converted to the nonlinear ordinary differential equations (NLODEs); and then, the resulting NLODEs are solved through an effective method called the exp(− ϕ ( ϵ ))-expansion method. As a consequence, a number of exact solutions to the fractional forms of EW and modified EW equations are generated.

In this paper, Newell–Whitehead–Segel equations of fractional order are solved by fractional variational iteration method. Convergence analysis and numerical examples are presented to show the efficiency of the proposed numerical method. Plotted graph demonstrate the mightiness and accurateness of the proposed technique.

The flow of nanofluids past a stretching sheet has attracted much attention due to its wide applications in industry and engineering. Theoretical and numerical solutions have been discussed in this paper for studying the effect of suction or injection on flow of nanofluids past a stretching sheet. In the absence of thermophoresis the analytical exact solution of the stream function was obtained in terms of exponential function, while the exact solutions for temperature and nanoparticle volume fraction were obtained in terms of the generalized incomplete gamma function. In addition, in the presence of thermophoresis, the exact solutions are not available. Therefore, the numerical results, carried out by using Chebyshev collocation method ( ChCM ). It is found that a good agreement exists between the present results and with those published works. Useful results for temperature profile, concentration profile, reduced Nusselt number and reduced Sherwood number are discussed in details graphically. It was also demonstrated that both temperature and concentration profiles decrease by an increase from injection to suction. Finally, the present results showed that increase of the wall mass transfer from injection to suction decreased both reduced Nusselt number and the reduced Sherwood number when Brownian motion parameter and Lewis number increased.

A rigorous analysis of unsteady magnetohydrodynamic mixed convection and electrically conducting nanofluid model with a stretching/shrinking wedge is presented. First, the governing partial differential equations for momentum and energy conservation are converted to coupled nonlinear ordinary differential equations by means of exact similarity transformation. The homotopy analysis method (HAM) is employed to obtain the analytical approximations for flow velocity and temperature distributions of alumina-sodium alginate naofluid. The solution is found to be dependent on some parameters including the nanoparticle volume fraction, unsteadiness parameter, magnetic parameter, mixed convection parameter and the generalized prandtl number. A systematic study is carried out to illustrate the effects of these parameters on the velocity and temperature distributions. Also, the value of skin friction coefficient and local Nusselt number are compared with copper-sodium alginate and titania-sodium alginate nanofluids.

Modelling and control applications of dynamical systems in chaos theory arising in several areas are investigated and new control techniques are designed in the chaos literature. We propose a new complex finance chaotic model with states as the interest rate, investment demand, and price index. In this work, after studying the dynamical properties of the new finance model, an electronic chaotic circuit of the model is realized in Multisim. Based on passive control theory, we derive a new controller for globally synchronizing state trajectories of the new finance models. Using the new finance chaotic model developed in this work, a new voice encryption algorithm design is presented. With the proposed algorithm, voice encryption application is performed, and results are described.

Thermal effects have been investigated in a porous inclined slider bearing together with the slip boundary conditions. Using Jenkins model, the governing system of equations pertaining to the flow is solved analytically to yield the various bearing characteristics. The expressions for mean temperature, pressure and the lifting force (load carrying capacity) have been derived as a function of slip, magnetic, permeability, material and thermal parameters. Furthermore, the term pertaining to the co-rotational derivative of magnetization is expected to influence the lifting force significantly. Therefore its effect on the bearing characteristics is also considered. The lubricant is assumed to be incompressible, and its viscosity varies exponentially with the temperature. The behavior of mean temperature with other bearing characteristics across the fluid film thickness has also been investigated. The variations in the lifting force and mean temperature w.r.t. various bearing parameters have been analyzed graphically.

In this paper, a spectral method based on the rational Legendre functions is discussed to approximate the solution of the boundary layer flow of an Eyring-Powell non-Newtonian fluid over a stretching sheet. At first, because of the model is a nonlinear ordinary differential equation, we construct a sequence of linear ordinary differential equations (ODEs) by using the quasilinearization method (QLM). By applying QLM on the ODEs at each iteration, the equations convert to a system of linear algebraic equations. The present results have shown the high attention and convergence of our method, and the residual error of the present results are very small. In addition, the effect of the Eyring-Powell fluid material parameters is explained.

The aim of this paper is to investigate hyperbolic rational solutions of four conformable fractional Boussinesq-like equations using the method of exponential rational function (ERF). The present method is a good scheme, reveal distinct exact solutions and convenient for solving other types of nonlinear conformable fractional differential equations. These solutions are of significant importance in coastal and ocean engineering where the fractional Boussinesq-like equations modeled for some special physical phenomenon.

This paper provides analytical solution of the non-aligned stagnation point flow of second grade fluid over a porous rotating disk in the presence of a magnetic field and suction/injection at the disk surface. The mathematical formulation of the fluid model is obtained in terms of partial differential equations (PDEs). The PDEs governing the motion are transformed into a system of ordinary differential equations (ODEs) by means of a similarity transformation and these corresponding nonlinear ODEs are solved by employing the homotopy analysis method (HAM) and the convergence analysis of the presented method is also performed graphically. An inclusion of the influences of various admissible parameters has been shown numerically and graphically on the flow field. Furthermore, comparison is made and it concedes that the obtained results are found to be in good agreement with results existing in literature.

In recent years, structures made of Functionally Graded materials (FGMs) are used in industries due to the continuously compositional variation of the constituents in FGMs along different directions. In order to develop FGMs, nonlinear vibration analysis to study dynamic behavior is needed. This study proposes nonlinear vibration analysis of a simply supported axially functionally graded (AFG) beam subjected to a moving harmonic load as an Euler-Bernoulli beam utilizing Green’s strain tensor. Axial variation of material properties of the beam is based on the power law. The governing equations of motion are derived via Hamilton’s principle. The Galerkin’s method is implemented to reduce the nonlinear partial differential equations of the system to a number of nonlinear ordinary differential equations. He’s variational method is applied to obtain approximate analytical expressions for the nonlinear frequency and the nonlinear dynamic response of the AFG beam. The effect of some parameters such as the power index and stiffness coefficients, among others, on the nonlinear natural frequency has been investigated. The influence of above mentioned parameters as well as the velocity of the moving harmonic load on the nonlinear dynamic response has been studied. The results indicate that these parameters have a considerable effect on both nonlinear natural frequency and response amplitude.

The main objective of the present investigation is to examine the couple stress fluid flow occurring as a result of rotation of a disk. On implementing a suitable transformation, the governing system of partial differential equations (PDEs) is converted into nonlinear differential equations of a single independent variable. These equations are solved analytically by virtue of the Homotopy Analysis Method (HAM) which gives solutions in the form of a series. The solution of most of the governing problems is determined in terms of the absolute exponential and decaying functions by means of this powerful technique. To support analytic results, some graphs are plotted for determining the convergence of the solution. Also the graphical interpretation of velocity profiles corresponding to the effects of pertinent parameters are shown and discussed in detail. The numerical results are calculated for evaluation of the influence of fluid parameter. It can also be anticipated that the radial and axial velocity components show decreasing behavior due to rise in the values of couple stress parameter which conflict the behavior of the tangential component of velocity.

In this paper, we have studied the heat transfer characteristics of stagnation point flow of an MHD flow over a non-linearly moving plate with momentum and thermal slip effects in presence of non-uniform heat source/sink. The governing differential equations are transformed into the ordinary differential equations using suitable similarity transformations. These equations which are BVPs’ and are solved using a numerically by fourth order Runge-Kutta method using MAPLE computing software. The effects of governing parameters are studied on flow, velocity and heat distributions and are discussed in detail. It is observed that the non-uniform heat source parameters enhance the temperature distribution. Our results are agreed well with previously published results for some limiting conditions, which validate our present results are correct.

In the study, we inspect the impact of cross diffusion and aligned magnetic field on Casson fluid flow along a stretched surface of variable thickness. The differential equations explaining the flow situation have been transitioned with the succor of suited transfigurations. The solution of the problem is achieved by using bvp5c Matlab package. From the solution, it is perceived that the flow, temperature and concentration fields are affected by the sundry physical quantities. Results explored for the flow over a uniform and a non-uniform thickness surfaces. The influence of emerging parameters on the flow, energy and mass transport are discussed with graphical and tabular results. Results show that the thermal, flow and species boundary layers are uneven for the flow over a uniform and non-uniform thickness stretched surfaces.

A model for double-diffusive convection in anisotropic and inhomogeneous porous media has been analysed. In particular, the effect of variable permeability and thermal diffusivity has been studied using the Brinkman model. Moreover, we analyse the effect of slip boundary conditions on the stability of the model. Due to numerous applications in micro-electro-mechanical-systems (MEMS) and other microfluidic devices, such a study is essential to have. Both linear instability analysis and nonlinear stability analysis are employed. We accurately analyse when stability and instability will commence and determine the critical Rayleigh number as a function of the slip coefficient.

This study analyzed the MHD boundary layer flow of Eyring-Powell nanofluid past stretching cylinder with Cattaneo-Christov heat flux model. The governing non-linear partial differential equations corresponding to the momentum, energy and concentration have been formulated and transformed into a set of non-linear ordinary differential equations by using similarity transformations. Then the resulting non-linear high order ordinary differential equations of momentum, energy and concentration, subjected to boundary conditions were solved numerically by utilizing the second-order accurate implicit finite difference method known as Keller-Box which is programmed in the MATLABR2017b software. The results indicated that the velocity profile increases as the Eyring-Powell fluid parameter M and the curvature parameter γ increase but it decreases as the magnetic parameter Ha increases. Both the temperature and the concentration profiles have revealed an increment pattern for large values of the magnetic parameter Ha and the thermophoresis parameter N t but a decrement manner with increasing values of the Eyring-Powell fluid parameter M . The Brownian motion parameter N b has shown an opposite influence on the temperature and the concentration profiles. The results also depicted that the local skin friction coefficient increases with increasing in Eyring-Powell fluid parameter M , magnetic parameter Ha . Besides, it is found that both the local Nusselt number Nu x and the local Sherwood number Sh x are higher for large vales of Eyring-Powell fluid parameter M and curvature parameter γ . Furthermore, the present results for the local skin friction coefficient, the local Nusselt number and the local Sherwood number are validated with the data of previously published literature for various limiting conditions where a very sound agreement has been attained.

Herein, three important theorems were stated and proved. The first relates the modified generalized Laguerre expansion coefficients of the derivatives of a function in terms of its original expansion coefficients; and an explicit expression for the derivatives of modified generalized Laguerre polynomials of any degree and for any order as a linear combination of modified generalized Laguerre polynomials themselves is also deduced. The second theorem gives new modified generalized Laguerre coefficients of the moments of one single modified generalized Laguerre polynomials of any degree. Finally, the third theorem expresses explicitly the modified generalized Laguerre coefficients of the moments of a general-order derivative of an infinitely differentiable function in terms of its modified generalized Laguerre coefficients. Some spectral applications of these theorems for solving ordinary differential equations with varying coefficients and some specific applied differential problems, by reducing them to recurrence relations in their expansion coefficients of the solution are considered.

In this paper, a time dependent singularly perturbed differential-difference convection-diffusion equation is solved numerically by using an adaptive grid method. Similar boundary value problems arise in computational neuroscience in determination of the behaviour of a neuron to random synaptic inputs. The mesh is constructed adaptively by using the concept of entorpy function. In the proposed scheme, prior information of the width and position of the layers are not required. The method is independent of perturbation parameter ε and gives us an oscillation free solution, without any user introduced parameters. Numerical examples are presented to show the accuracy and efficiency of the proposed scheme.

Present article reports the magnetohydrodynamic flow of Carreau nanofluid in the presence of nonlinear thermal radiation. In this model we incorporated slip condition on heat and mass boundary conditions. Similarity transformations are applied to convert the governing dimensional expressions into non-dimensional forms. Runge-Kutta-Fehlberg method of fourth–fifth order using shooting technique utilized to elaborate the numerical solutions of physical phenomenon.A comparative analysis is presented with the previous published data in special case for the justification of present results. The role of physical constraints on liquid velocity, temperature and concentration are discussed through numerical data and plots.

In this paper, the rational exponential solutions of two space-time fractional equal-width (FEW) equations are explored in the conformable derivative sense. The way to reach explicit exact solutions is to transform the fractional order PDEs into a nonlinear ODEs of discrete order through some properties of conformable derivatives and a fractional complex transforms. The subsequent equations have been elucidated by employing the exp a function approach. Some new exact solutions of the said equations are effectively formulated and graphically conveyed with the aid of symbolic computation in Mathematica and MATLAB respectively.

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-CH 3 OH and Cu-CH 3 OH 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.

In this paper, the counter-current Imbibition phenomenon is considered in a fractured heterogeneous porous medium with the consideration of different porous materials like fine sand, volcanic sand and glass beads and magnetic field effect. The Homotopy analysis method is used here to derive an expression for finding the saturation profiles in a fractured heterogeneous porous medium with and without considering the magnetic field effect. Simulation results are developed for the saturation profiles to study the effect of inclination and the viscosity variation of native fluids on the saturation rate and the recovery rate of the reservoir with some interesting choices of parameters.

Present communication aims to discuss the impact of viscous dissipation on MHD flow, heat and mass transfer of Casson fluid over a plate by considering mixed convection. Nonlinear partial differential systems are reduced to the ordinary ones through transformation procedure. The modelled nonlinear systems are computed implementing RKF-45 scheme. Convergent solutions for velocity and temperature and concentration fields are given diagrammatically. The obtained results are compared with published literatures and reasonable agreement is found. It is found that, temperature profile increases by increasing values of Dufour parameter, whereas on opposite trend is observed in concentration profile for increasing values Soret parameter.

This paper provides an explanation of the geometry, design, and operational principles for the three engines; having special emphasis in the Szorenyi rotary engine which has a deforming rhombus revolving inside a mathematically defined stator. A basic ideal mathematical simulation of those engines were performed, assuming the Otto cycle for the three engines. Also, it assumes the volumetric efficiency of 100%, a wide-open throttle (WOT), no knock nor any mechanical or thermal losses. This simulation focuses on how the fuel burns during combustion, creating pressure and thus, net work. A comparison in pressure traces and cycle performance is made. The study concludes analysing and comparing the ignition advance; finding the best advance for each engine thus the net work between the three engines during one working cycle. Finally, this paper analyses how the different volume change ratio for the combustion chamber of the Szorenyi, Wankel and the reciprocating engine have an effect in the pressure, net work and thermal efficiency generated inside the chamber during combustion for every working cycle.

The paper presents, surface roughness effect for thermo-hydrodynamic analysis of journal bearings extended to couple stress lubricants with high polymer additives. A modified energy equation is simultaneously solved with heat transfer equation as well as modified Reynolds equation by using Multigrid method. The effects of couple stress and surface roughness on the performances of a finite journal bearing are presented in detail. Further, it is shown that lubricants with couple stress and surface roughness, not only increases the load capacity and decreases the friction coefficient, but also generates a lower bearing temperature field. Thus, the lubricant with couple stress improves the performance of journal bearings. The characteristics of bearing are compared with numerical results.

In this present analysis we investigated the steady-state magnetohydrodynamic boundary layer flow of tangent hyperbolic fluid over an exponentially stretching surface in the presence of heat source and chemical reaction. The chemical reaction with combination of exponential surface has significance in many industrial and manufacturing systems. The partial nonlinear differential equations are transformed into ordinary differential equations by using the similarity conversion and the accomplished boundary layer ordinary differential equations are elucidated numerically by using Shooting technique. The effects of numerous non-dimensional governing factors on velocity, temperature and concentration profiles were depicted graphically and analyzed in detail. The numerically computed results of Skin friction factor, Nusselt and Sherwood numbers are presented in tabular form for suction and injection cases separately.Heat transfer rate at the surface increases with increasing values of power law of index and whereas it declines with the magnetic field, heat source and chemical reaction parameters. It observed that Biot number enhances the skin friction, Nusselt number and decrease the Sherwood number.Heat transfer rate and mass transfer rate increases and skin friction decreases with increasing Eckert number.

This study gives unsteady radiative magneto hydrodynamic Carreau-Casson fluids in suspension of graphene particle with Cattaneo-Christov model. A simulation is performed by mixing of graphene nanoparticles into the base water. The arising set of governing partial differential equations (PDEs) are transformed into set of ordinary differential equations (ODEs) using similarity transformations and then solved numerically using shooting technique with Runge-Kutta (RK) method. The computational results for non-dimensional temperature and velocity profiles are presented through graphs and tables. We also presented the numerical values of physical quantities (friction factor and local numbers) for various physical parameters. We compared the present results with existing literature under some limited case. At the end of this analysis we concluded that, the temperature profiles are higher in Casson fluid when compared to Carreau fluid. Similarly, the friction between the particles is more in Casson fluid compare to Carreau fluid, and heat transfer rate is high in Carreau fluid compared to Casson fluid. This help us to conclude that the cooling treatment by using Casson fluid is useful compared to Carreau fluid over unsteady sheet.

The purpose of this paper is to propose an efficient numerical method for solving system of Lane–Emden type equations using Chebyshev operational matrix method. This method transforms the system of Lane-Emden type equation into the system of algebraic equations with unknown Chebyshev coefficients. Some illustrative examples are given to demonstrate the efficiency and validity of the proposed algorithm.

Fractional calculus and fractional differential equations (FDE) have many applications in different branches of sciences. But, often a real nonlinear FDE has not the exact or analytical solution and must be solved numerically. Therefore, we aim to introduce a new numerical algorithm based on generalized Bessel function of the first kind (GBF), spectral methods and Newton–Krylov subspace method to solve nonlinear FDEs. In this paper, we use the GBFs as the basis functions. Then, we introduce explicit formulas to calculate Riemann–Liouville fractional integral and derivative of GBFs that are very helpful in computation and saving time. In the presented method, a nonlinear FDE will be converted to a nonlinear system of algebraic equations using collocation method based on GBF, then the solution of this nonlinear algebraic system will be achieved by using Newton-generalized minimum residual (Newton–Krylov) method. To illustrate the reliability and efficiency of the proposed method, we apply it to solve some examples of nonlinear Abel FDE.

A mathematical model is developed to study laminar, nonlinear, non-isothermal, steady-state free convection boundary layer flow and heat transfer of a micropolar viscoelastic fluid from a vertical isothermal cone. The Eringen model and Jeffery’s viscoelastic model are combined to simulate the non-Newtonian characteristics of polymers, which constitutes a novelty of the present work. The transformed conservation equations for linear momentum, angular momentum and energy are solved numerically under physically viable boundary conditions using a finite difference scheme (Keller Box method). The effects of Deborah number (De), Eringen vortex viscosity parameter (R), ratio of relaxation to retardation times ( λ ), micro-inertia density parameter (B), Prandtl number (Pr) and dimensionless stream wise coordinate ( ξ ) on velocity, surface temperature and angular velocity in the boundary layer regime are evaluated. The computations show that with greater ratio of retardation to relaxation times, the linear and angular velocity are enhanced whereas temperature (and also thermal boundary layer thickness) is reduced. Greater values of the Eringen parameter decelerate both the linear velocity and micro-rotation values and enhance temperatures. Increasing Deborah number decelerates the linear flow and Nusselt number whereas it increases temperatures and boosts micro-rotation magnitudes. The study is relevant to non-Newtonian polymeric thermal coating processes.

In this research, nonlinear dynamics and characteristics of a micro–plate system under electrostatic forces on both sides are studied. A novel model, which takes micro-scale effect and damage effect into account, is established on the basis of the Talreja’s tensor valued internal state damage model and modified couple stress theory. According to Hamilton principle, the dynamic governing equations of the size-dependent micro–plate are derived by variational method and solved via Galerkin method and the fourth order Runge-Kutta method. The effects of damage variable and material length scale parameter on bifurcation and chaos of the micro–plate system are presented with numerical simulations using the bifurcation diagram, Poincare map. Results provide a theoretical basis for the design of dynamic stability of electrically actuated micro- structures.

This article aims to study theoretically the combined magneto hydrodynamic flows of casson viscoplastic nanofluid from a horizontal isothermal circular cylinder in non-Darcy porous medium. The impacts of Brownian motion and thermophoresis are consolidated and studied. The governing partial differential equations are converted into nonlinear ordinary differential equations using suitable non-similarity transformation and are solved numerically using Keller-Box finite difference technique. The numerical method is validated with previous published work and the results are found to be in excellent agreement. Numerical results for velocity, temperature, concentration along with skin friction coefficient, heat and mass transfer rate are discussed for various values of physical parameters. It is observed that velocity, heat and mass transfer rate are increased with increasing casson fluid parameter whereas temperature, concentration and skin friction are decreased. Velocity is reduced with increasing Forchheimer parameter whereas temperature and nano-particle concentration are both enhanced. An increase in magnetic parameter is seen to increase temperature and concentration whereas velocity, skin friction heat and mass transfer rate are decreased. The present model finds applications in electric-conductive nano-materials of potential use in aviation and different enterprises, energy systems and thermal enhancement of industrial flow processes.

Internet of Things (IoT) opens up the possibility of agglomerations of different types of devices, Internet and human elements to provide extreme interconnectivity among them towards achieving a completely connected world of things. The mainstream adaptation of IoT technology and its widespread use has also opened up a whole new platform for cyber perpetrators mostly used for distributed denial of service (DDoS) attacks. In this paper, under the influence of internal and external nodes, a two - fold epidemic model is developed where attack on IoT devices is first achieved and then IoT based distributed attack of malicious objects on targeted resources in a network has been established. This model is mainly based on Mirai botnet made of IoT devices which came into the limelight with three major DDoS attacks in 2016. The model is analyzed at equilibrium points to find the conditions for their local and global stability. Impact of external nodes on the over-all model is critically analyzed. Numerical simulations are performed to validate the vitality of the model developed.

The present paper is aimed to study the buckling and postbuckling response of functionally graded carbon nanotube (FG-CNT)- magnesium (Mg) nanocomposite plate with interphase effect. Interphase zone is characterized by employing a cohesive zone model for its elastic modulus and thickness. An equivalent solid fiber (ESF) of CNT and interphase is modeled and dispersed into the matrix material by utilizing random sequential adsorption (RSA) technique. The effective elastic properties of the nanocomposite are computed by finite element method (FEM) based numerical homogenization technique. The obtained elastic properties of nanocomposite are utilized to investigate the buckling and post-buckling behaviour of different functionally graded (i.e., FG) nanocomposite plates modeled by varying the volume fraction of CNT/ESF along thickness direction, under in-plane compressive loads. The non-linear formulation is based on first-order shear deformation theory and von Karman’s assumptions. It is found that considering the interphase between CNT and Mg matrix would result in decrease in buckling load and postbuckling strength of FG-CNT-reinforced nanocomposite plate as compared to nanocomposite without interphase. It is also reported that the higher volume fraction of CNTs near top and bottom surfaces than the middle portion of nanocomposite plate provide better resistance to buckling and postbuckling.

In the present paper, a weakly nonlinear stability analysis is used to analyze the effect of time-periodic concentration/gravity modulation on mass transport. We have considered an infinite horizontal fluid layer with constant appliedmagnetic flux salted from above, subjected to an imposed time-periodic boundary concentration (ITBC) or gravity modulation (ITGM). In the case of ITBC, the concentration gradient between the plates of the fluid layer consists of a steady part and a time-dependent oscillatory part. The concentration of both walls is modulated. In the case of ITGM, the gravity fleld consists of two parts: a constant part and an externally imposed time periodic part, which can be realized by oscillating the fluid layer. We have expanded the infinitesimal disturbances in terms of power series of an amplitude of modulation, which is assumed to be small. Ginzburg-Landau equation is derived for dinding the rate of mass transfer. Effect of various parameters on the mass transport is also discussed. It is found that the mass transport can be controlled by suitably adjusting the frequency and amplitude of modulation.

The present article explores the effects of uniform heat source and first order destructive chemical reaction on an upper convected Maxwell fluid through an expanding or contracting channel with the porous slip condition at the upper plate. It is assumed that the fluid is sucked or injected through the upper plate. The temperature and concentration at the plates is maintained constant. Using suitable similarity transformations, nonlinear coupled ODEs are developed from the governing PDEs. The subsequent ODEs are converted into a first order system and integrated via shooting method. The effect of various prominent parameters on heat, flow and mass transfer characteristics are studied in detail through graphs and tables. The present results suggest that the presence of chemical reaction and heat source yields in the reduction of concentration and of the enhancement of temperature the fluid. It is also observed that the wall expansion shows an increasing effect on the radial velocity component, but the slip parameter exhibits an opposing effect. The viscous case has been studied as a special case where the present results are found to be close to the earlier ones. The flow of such nonlinear viscoelastic fluids has important applications in separation processes like petroleum and medical industries.

In the current study is to examine numerically the effects of presence of a radial magnetic field, slip and jump conditions on the steady two-dimensional free convective boundary layer flow over an external surface of a vertical cone for an electro-conductive polymer. A proper non-similarity transformation simplifies the system of partial differential equations into a system of ordinary differential equations. The collocation formula in the MATLAB software then solves the system of non-similarity equations. The finding results show that, a weak elevation in temperature is accompanied with the increase in the Carreau fluid parameter, whereas a significant acceleration in the flow is computed near the cone surface. The study is relevant to smart coating transport phenomena.

The present work involves the study of penetrative convection in an incompressible fluid-saturated porous media with local thermal non-equilibrium. The onset of convection evaluated linearly and nonlinearly for the system influenced by heat extraction and heat generation. Darcy-Brinkman law is employed to model the momentum equation and four type of internal heat generating function are considered which leads to thermo-convective instability within the fluid layer. Linear analysis carried out by using normal mode technique and nonlinear stability analysis has been done by energy method. Due to heat generation within the fluid layer and heat extraction through boundary, the subcritical instability may exist with higher possibility. Effects of various parameters as: inter-phase heat transfer parameter, Darcy-Brinkman number, porosity-modified conductivity ratio, and heat parameter are explored on Darcy-Rayleigh number by Chebyshev pseudospectral method as numerical form and graphical form.

In this work, we consider the (3+1) dimensional conformable fractional Zakharov-Kuznetsov equation with power law nonlinearity. Solitary wave solutions, soliton wave solutions, elliptic wave solutions, and periodic (hyperbolic) wave rational solutions are obtained by means of the unified method. The solutions showed that this method provides us with a powerful mathematical tool for solving nonlinear conformable fractional evolution equations in various fields of applied sciences.

Articulated heavy vehicles have some specific performance limitations and safety risks due to their special dynamic characteristics. They show poor manoeuvrability at low speeds and may lose their stability in different manners at high speeds. In this study, the potential of active steering control of the semitrailer on manoeuvrability and stability of tractor-semitrailer combinations is investigated. A linear bicycle model and a nonlinear version are used for controller design and vehicle dynamic simulation in MATLAB environment. The Linear Quadratic Regulator optimal state feedback control is used to minimise the tracking error at low-speed, and regulate Rearward Amplification ratio and roll at high-speed. Quantum Particle Swarm Optimisation is used for optimising the weighting factors. Three different control algorithms are introduced and it is demonstrated through simulations that the vehicle with the proposed steering control exhibits desirable improvements compared to the baseline vehicle.

Nonlinear stability of nanocomposite spherical and cylindrical panels reinforced by carbon nanotubes (CNTs), resting on elastic foundations and subjected to uniform external pressure in thermal environments is investigated in this paper. CNTs are embedded into matrix phase through uniform distribution (UD) or functionally graded (FG) distribution, and effective properties of CNT-reinforced composite are estimated through an extended rule of mixture. Governing equations are based on classical shell theory taking geometrical nonlinearity, initial geometrical imperfection and panel-foundation interaction into consideration. Approximate solutions of deflection and stress functions are assumed to satisfy simply supported boundary conditions and Galerkin method is applied to obtain nonlinear load-deflection relation. Numerical examples show the effects of volume fraction and distribution type of CNTs, in-plane condition of edges, curvature of panel, thermal environments, elastic foundations and imperfection size on the nonlinear response and snap-through instability of the curved panels. The present study reveals that efficiency of CNT distribution type depends on curvature of panel and in-plane behavior of boundary edges, and bifurcation type buckling response of pressure-loaded panels may occur at elevated temperature.

In this article, a scheme using active backstepping design method is proposed to achieve combination synchronization of n number of fractional order chaotic systems. In the proposed method the controllers are designed with the help of a new lemma and Lyapunov function in a systematic way. Synchronization among three/four fractional order systems have been shown as examples of synchronization of n-chaotic systems. Numerical simulation and graphical results clearly exhibit that the method of this new procedure is easy to implement and reliable for synchronization of fractional order chaotic systems.

A vision based formation and attitude controller has been derived and simulated for the formation keeping of two 3U CubeSats. Four markers are installed on the leader CubeSat. Two cameras are installed on the follower CubeSat. An efficient vision based pose estimation method is used to estimate the pose of the follower with respect to the leader. A Higher-Order Sliding Mode (HOSM) exact differentiator with finite-time convergence is derived to estimate the rate of the follower’s pose parameters. The follower’s pose and its time rate are fedback to HOSM formation and attitude controllers to correct any gradual drift in formation and pose of the follower. The simulations show the effectiveness of the approach, and its feasibility on existing hardware.

In this investigation, we have studied the problem of peristaltic flow with heat transfer through the gap between coaxial inclined tubes where the inner tube is rigid and the outer tube has sinusoidal wave travelling down its wall. The problem has been formulated in cylindrical coordinate system. The equations governing the flow have been simplified under the long wavelength and low Reynolds number assumptions. The exact solution is obtained for the temperature profile. The perturbation solutions for the velocity and pressure gradient are obtained for small couple stress parameter. Pressure difference per wavelength and frictional forces on the tube walls have been computed numerically. Results are demonstrated for various flow parameters. The better pumping results occur in vertical tube, while less pumping is seen in horizontal tube. The size of trapped bolus is small in triangular wave as compared to other waves. The present study has a wide range of applications in bio-medical engineering like the transport phenomenon in peristaltic micro pumps.

A theoretical study of unsteady magnetohydrodynamic boundary layer stagnation point flow, heat and mass transfer of a second grade electrically-conducting nanofluid from a horizontal stretching sheet with thermal slip and second order slip velocity effects is presented. The Buongiorno formulation is employed for nanofluids and in addition the no-flux nanoparticle boundary condition is also considered. The appropriate similarity transformations are applied to convert the governing equations into the system of nonlinear partial differential equations, which is solved by using homotopy analysis method. Entropy generation and Bejan number have also been evaluated for the effects of magnetic parameter, Reynolds number and slip parameter in non-Newtonian (second-grade) time-dependent flow. The computations show that skin friction coefficient and entropy generation number increase with an increment in magnetic parameter whereas Bejan number decreases with it. Local Nusselt number decreases with an increase in the value of Eckert number (viscous dissipation) and thermal slip whereas the converse behaviour is captured for velocity parameter. The work is relevant to magnetohydrodynamic nanomaterials processing.

In this article, the combined magnetohydrodynamic heat, momentum and mass (species) transfer in external boundary layer flow of Casson nanofluid from an isothermal sphere surface with convective condition under an applied magnetic field is studied theoretically. The effects of Brownian motion and thermophoresis are incorporated in the model in the presence of both heat and nanoparticle mass transfer convective conditions. The governing partial differential equations (PDEs) are transformed into highly nonlinear, coupled, multi-degree non-similar partial differential equations consisting of the momentum, energy and concentration equations via appropriate non-similarity transformations. These transformed conservation equations are solved subject to appropriate boundary conditions with a second order accurate finite difference method of the implicit type. The influences of the emerging parameters i.e. magnetic parameter ( M ), Buoyancy ratio parameter (N) , Casson fluid parameter ( β ), Brownian motion parameter ( Nb ) and thermophoresis parameter ( Nt ), Lewis number ( Le ), Prandtl number ( Pr ) and thermal slip ( S T ) on velocity, temperature and nano-particle concentration distributions is illustrated graphically and interpreted at length. Increasing viscoplastic (Casson) parameter decelerates the flow and also decreases thermal and nano-particle concentration. Increasing Brownian motion accelerates the flow and enhances temperatures whereas it reduces nanoparticle concentration boundary layer thickness. Increasing thermophoretic parameter increasing momentum (hydrodynamic) boundary layer thickness and nanoparticle boundary layer thickness whereas it reduces thermal boundary layer thickness. Increasing magnetohydrodynamic body force parameter decelerates the flow whereas it enhances temperature and nano-particle (species) concentrations. The study is relevant to enrobing processes for electric-conductive nano-materials, of potential use in aerospace and other industries.

Present analysis is to study the combined effects of viscous dissipation and Joule heating on MHD three-dimensional laminar flow of a viscous incompressible non-linear radiating Casson nanofluid past a nonlinear stretching porous sheet. Present model describes that flow generated by bi-directional non-linear stretching sheet with thermophoresis and Brownian motion effects. The governing nonlinear partial differential equations are transformed into a system of nonlinear coupled ordinary differential equations by similarity transformations and then solved by employing shooting method. The effects of the flow parameters on the velocity, temperature and concentration as well as the skin friction coefficient, Nusselt number and Sherwood number near the wall are computed for various values of the fluid properties. This study reveals that the temperature of Casson nanofluid increases with combination of viscous dissipation and Joule heating. Increasing thermophoresis parameter increases the species concentration of the nanoflow. The comparison of present results have been made with the published work and the results are found to be very good agreement.

In this article, we study the nonlinear steady thermal convection of an incompressible third-grade non-Newtonian fluid from a horizontal circular cylinder. The transformed conservation equations are solved numerically subject to physically appropriate boundary conditions using a second-order accurate implicit finite-differences Keller Box technique. The influence of a number of emerging non-dimensional parameters, namely the third-grade fluid parameter ( ϕ ), the material fluid parameters ( ϵ 1 , ϵ 2 ), Prandtl number ( Pr ), Biot number ( y ), thermal radiation ( F ) and dimensionless tangential coordinate ( ξ ) on velocity and temperature evolution in the boundary layer regime are examined in detail. Furthermore, the effects of these parameters on surface heat transfer rate and local skin friction are also investigated. Validation with earlier Newtonian studies is presented and excellent correlation is achieved. It is found that the velocity, skin friction and Nusselt number (heat transfer rate) reduce with increasing third grade fluid parameter ( ϕ ), whereas the temperature is enhanced. Increasing material fluid parameter ( ϵ 1 ) reduces the velocity and heat transfer rate but enhances the temperature and skin friction. The study is relevant to chemical materials processing applications and low density polymer materials processing.

In this paper, a novel method based on Bessel functions (BF), generalized Bessel functions (GBF), the collocation method and the Jacobian free Newton-Krylov sub-space (JFNK) will be introduced to solve the nonlinear time-fractional Burger equation. In this paper, an implicit formula is introduced to calculate Riemann–Liouville fractional derivative of GBFs, that can be very useful in spectral methods. In this work, the nonlinear time-fractional Burger equation is converted to a nonlinear system of algebraic equations via collocation algorithm based on BFs and GBFs without any linearization and descretization methods. Finally, by using JFNK, the solution of this nonlinear system will be achieved. To show the reliability and applicability of the proposed method, we solve some examples of time-fractional Burger equation and compare our results with others.

In this paper, numerical solution of fractional order Navier-Stokes equations in unsteady viscous fluid flow is found using q-homotopy analysis transform scheme. Fractional derivative is considered in Caputo sense. The proposed technique is a blend of q-homotopy analysis scheme and transform of Laplace. It executes well in efficiency and provides h -curves that show convergence range of series solution.

The nonlocal nature of the fractional derivative makes the numerical treatment of fractional differential equations expensive in terms of computational accuracy in large domains. This paper presents a new multiple-step adaptive pseudospectral method for solving nonlinear multi-order fractional initial value problems (FIVPs), based on piecewise Legendre–Gauss interpolation. The fractional derivatives are described in the Caputo sense. We derive an adaptive pseudospectral scheme for approximating the fractional derivatives at the shifted Legendre–Gauss collocation points. By choosing a step-size, the original FIVP is replaced with a sequence of FIVPs in subintervals. Then the obtained FIVPs are consecutively reduced to systems of algebraic equations using collocation. Some error estimates are investigated. It is shown that in the present multiple-step pseudospectral method the accuracy of the solution can be improved either by decreasing the step-size or by increasing the number of collocation points within subintervals. The main advantage of the present method is its superior accuracy and suitability for large-domain calculations. Numerical examples are given to demonstrate the validity and high accuracy of the proposed technique.

The key objective of this paper is to study the fractional model of Fitzhugh-Nagumo equation (FNE) with a reliable computationally effective numerical scheme, which is compilation of homotopy perturbation method with Laplace transform approach. Homotopy polynomials are employed to simplify the nonlinear terms. The convergence and error analysis of the proposed technique are presented. Numerical outcomes are shown graphically to prove the efficiency of proposed scheme.

The nonlinear fractional differential equations (FDEs) are produced by mathematical modelling of some nonlinear physical systems. The study of such nonlinear physical models through wave solutions analysis corresponding to their FDEs, has a dynamic role in applied sciences. In this paper, we are going to explore the conformable time-fractional KdV equations using the exp a function method. The way to reach explicit exact wave solutions is to transform the fractional order PDE into a nonlinear ODE of discrete order through travelling wave transforms. The subsequent equation has been explored by utilizing the exp a function approach. Consequently, some new explicit exact wave solutions of the said equations are effectively formulated and graphically conveyed with the help of numerical simulation.

The present comment concerns some doubtful results included in the above paper.

This article presents the effect of nonlinear thermal radiation on three dimensional flow and heat transfer of fluid particle suspension over a stretching sheet. The combined effects of non-uniform source/sink and convective boundary condition are taken into consideration. The governing partial differential equations are transformed into ordinary differential equations using similarity variables, which are then solved numerically by using Runge Kutta Fehlberg-45 method with shooting technique. The influence of various parameters on velocity and temperature profiles are illustrated graphically, and discussed in detail. The results indicate that the fluid phase velocity is greater than that of the particle phase for various existing parameters.

Current article is devoted with the study of MHD 3D flow of Oldroyd B type nanofluid induced by bi-directional stretching sheet. Expertise similarity transformation is confined to reduce the governing partial differential equations into ordinary nonlinear differential equations. These dimensionless equations are then solved by the Differential Transform Method combined with the Padé approximation (DTM-Padé). Dealings of the arising physical parameters namely the Deborah numbers β 1 and β 2 , Prandtl number Pr, Brownian motion parameter N b and thermophoresis parameter N t on the fluid velocity, temperature and concentration profile are depicted through graphs. Also a comparative study between DTM and numerical method are presented by graph and other semi-analytical techniques through tables. It is envisage that the velocity profile declines with rising magnetic factor, temperature profile increases with magnetic parameter, Deborah number of first kind and Brownian motion parameter while decreases with Deborah number of second kind and Prandtl number. A comparative study also visualizes comparative study in details.

This study is devoted to investigate the influence of transverse magnetic field as well as suction/injection on MHD natural convection flow of conducting fluid in an inclined micro-porous-channel. The analytical solutions for velocity profile and temperature profile have been obtained considering the velocity slip and temperature jump conditions at the micro-porous-channel walls. The solution obtained for the velocity has been used to compute the skin friction, while the temperature has been used to compute the Nusselt number. The effect of various flow parameters entering into the problem are discussed with the aid of line graphs. Results reveal that the impact of inclination angle on fluid velocity is dependent on the value of the wall ambient temperature difference ratio, hence increase in inclination angle yields an enhancement in fluid velocity within the micro-porous-channel for some selected values of the wall ambient temperature difference ratio whereas it displays a dual character for other values. Also, injecting through the micro-porous channel thickens the thermal boundary layer, resulting to weakening the convective current and consequently decreasing the fluid velocity whereas suction weakens the thermal boundary layer yielding an increase in fluid velocity.