Presence Of Slip Effects Research Articles

Darcy–Brinkman porous medium for dusty fluid flow with steady boundary layer flow in the presence of slip effect

This study looks at the Darcy–Brinkman flow across a stretched sheet of porous dissipation and frictional heating. The geometry of a steady flow of dust particles fluid through a porous material in the existence of slip effect and porous dissipation is the subject of this study. The equations that govern the system are shown and summarized as boundary layer assumptions, and then modified into framework of first-order DEs using the similarity approach. By using similarity transformation, a two-dimensional nonlinear partial differential equation is decreased to a sequence of nonlinear ordinary differential equations (ODEs). Then, by employing numerical techniques such as Maple packages, the solution of system of nonlinear equations is represented using the RK4 method. The numerical findings are derived under specific unique situations. The Nusselt number and coefficient of skin-friction are also given numerically. The increase in Brinkman number [Formula: see text] raises the temperature profile for both the dusty and the fluid phases. The results also demonstrate that rise in the suction number S falls the temperature distribution within the boundary layer for the dusty phase and fluid phase. For a variety of flow quantities of attention, the variation of parameters is studied, and the outcomes are reported in the shape of graphs and tables. Several industrial processes make advantage of boundary layer flow and heat transfer over such a stretched surface in porous materials.

Significance of Lorentz forces on Jeffrey nanofluid flows over a convectively heated flat surface featured by multiple velocity slips and dual stretching constraint: a homotopy analysis approach

Abstract Motivated by the temporal relaxation feature of the Jeffrey model and its practical uses in the rheological modeling of several vital liquids, this study aimed to present a theoretical analysis of three-dimensional MHD Jeffrey nanofluid flows over a dual stretching surface with velocity slip conditions. By adopting the nonhomogeneous nanofluid model along with the passive control approach of nanoparticles, the current flow problem is solved semi-analytically via the homotopy analysis method for convective heating and multiple slip conditions. Dynamically, the magnetic and viscoelastic parameters have a declining effect on the velocity distributions in both directions in the existence and absence of slip effects, while the Deborah number has generally an escalating influence on the flow distributions. On the other hand, the variations of the velocity profiles in both directions are always greater in the presence of slip effect as compared to the nonslip case. Besides, the velocity stretching factor rises the velocity profiles in both directions. Furthermore, this increasing impact is dominant for the velocity distribution along the $y{\rm{-}}$direction as compared to the velocity field along the $x{\rm{-}}$direction. Thermally, the greater Biot number increases the temperature distribution. However, the bigger Schmidt number reduces the concentration distribution.

Simultaneous features of Wu's slip, nonlinear thermal radiation and activation energy in unsteady bio-convective flow of Maxwell nanofluid configured by a stretching cylinder

This continuation deals with the bioconvection flow of magnetized Maxwell nanofluid over a stretched cylinder in presence of slip effects. The novel features of activation energy and thermal radiation are also encountered to analyze the flow. The higher order slip relations are introduced to inspect the thermal flow problem. The flow model is developed in terms of dimensionless equations via appropriate variables. The numerical simulations are presented with shooting scheme by using MATLAB software. The physical outcomes of interesting parameters are visualized. The observations show that velocity profile reduces with unsteady parameter, curvature constant and second order slip factor. The temperature profile enhanced with first order velocity slip parameter and curvature constant. Moreover, nanofluid concentration reduces with Lewis number and Brownian constant.

Bioconvection analysis for flow of Oldroyd-B nanofluid configured by a convectively heated surface with partial slip effects

The improved thermal mechanism of nano-scale particles has attended a special focus of scientists in current time. Owing to the multiple dynamic applications of such nanoparticles in various era of engineering and thermal sciences like cooling/heating materials, heat production, energy resources and bio-medical sciences like cancer treatment, destroying of damage cells, brain tumors etc. Further, bio-convective phenomenon of nanoparticles is also referred to many applications in bio-sciences like enzymes, bio-sensors, bio-fuels etc. Keeping such motivating applications in mind, present communication addresses the bioconvection assessment in Oldroyd-B nanofluid conducted over a convectively heated configuration. Further, the partial slip mechanism is followed for to examine the flow pattern. The novel zero mass flux aspects have been taken into account at the solid surface of plate such that the nano-materials fraction is attended itself on higher retardation. After altering the equations in dimensionless form, shooting numerical algorithm is employed for the solution procedure. It is observed that variation in relaxation time constant increase the velocity profile which is more progressive in presence of slip effects. The presence of slip factor improves the heat and mass transportation more effectively. Moreover, the concentration profile decline with retardation time constant and Schmidt number.

Robust forward\\backward control of wheeled mobile robots

Obtaining a control algorithm capable of navigating the system both in forward and backward motions is one of the control objectives for tractor-trailer wheeled robots (TTWRs). In this paper, a relatively general structure is presented for both forward and backward control of an n-trailer wheeled mobile robot (NTWMR) in the presence of wheel slip effects. To keep better overall performance and track the reference trajectories in forward and backward motions, the NTWMR is intended to be controlled in the presence of slip effects. A control algorithm accompanied by a slip compensation procedure is proposed for the system simultaneously. First, the mathematical model of the system in the presence of slip effects is obtained. A novel physically motivated algorithm is proposed for the tracking control in the presence of unknown uncertainties (longitudinal and lateral slips) for both forward and backward motions. By estimating the slip effects at any instant, the control inputs are produced to compensate for their destructive effects on tracking control of the NTWMR. Then the stability of the closed-loop system is evaluated using the Lyapunov theory. The potential of the proposed controller was verified through several case studies, including comparative results and experimental validation in various motion control manoeuvers for a vehicle with trailers. The proposed method is the first algorithm that can cover a broad range of TTWR motion tasks (forward and backward trajectory tracking, slip attenuation, and global stability), which are required to be developed in NTWMRs.

HEAT TRANSFER AND SLIP CONSEQUENCES ON PERISTALTIC TRANSPORT OF A CASSON FLUID IN AN AXISYMMETRIC POROUS TUBE

The present study investigates the effects of heat transfer on a Casson fluid flow through a porous axisymmetric tube in the presence of slip effects. The long wavelength and small Reynolds number approximation is used to obtain the closed form solutions. The numerical integration is employed to obtain pressure rise and frictional force. A parametric analysis has been presented to study the effects of Darcy number, velocity slip, yield stress, Prandtl number, Eckert number, and thermal slip on pressure rise, pressure gradient, frictional force, and temperature. The study reveals that the reduction in pressure rise is observed for an increase in the value of porous parameter and an increase in the value of velocity slip parameter enhances the pressure rise in the porous tube. The obtained results are found to be in good agreement with the available literature

Meta-analysis on homogeneous-heterogeneous reaction effects in a sinusoidal wavy curved channel

This research discusses the merged effect of homogeneous-heterogeneous reactions on the peristaltic mechanism of hyperbolic tangent fluid in a curved compliant channel in the presence of slip effects. Transport of heat is developed by using the heat conduction model proposed by Fourier with viscous dissipation effect. The derived coupled system of partial differential equations have been simplified under long wavelength assumptions. Keeping in mind of the considered problem assumptions, it is found that the governing system of fluid flow equations are coupled and highly non-linear. A perturbation technique is applied for small Weissenberg number to find out the series solution for stream function, momentum, thermal, concentration distributions, and heat transfer coefficient. The influence of numerous parameters associated with flow characteristics such as Brinkman number, Prandtl number, Hartman number, and slip which are explained in detail and also, plotted the graph for velocity, concentration and temperature distribution. The expressions for skin friction coefficient and Nusselt number at the complaint wall are found and evaluated. It is worth mounting that augmenting values of velocity slip and elastic parameters reduces the fluid velocity, whereas, thermal profile upsurges against the mounting values of slip parameter. Moreover, it is recorded the elastic parameter has reverse behavior on thermal field as compared with brinkman number. The scope of the present article is valuable in explaining the blood transport dynamics in small vessels while considering the important wall features with chemical reaction characteristics.

Simultaneous Effects of Heat Transfer and Variable Viscosity on Peristaltic Transport of Casson Fluid Flow in an Inclined Porous Tube

The present study investigates the combined effects of varying viscosity and heat transfer on a Casson fluid through an inclined porous axisymmetric tube in the presence of slip effects. The modeled governing equations are solved analytically by considering the long wavelength and small Reynolds number approximations. The numerical integration is employed to obtain pressure rise and frictional force. A parametric analysis has been presented to study the effects of the Darcy number, angle of inclination, varying viscosity, velocity slip, thermal slip, yield stress, amplitude ratio, Prandtl number and Eckert number on the pressure rise, pressure gradient, streamlines, frictional force and temperature. The study reveals that an increase in the angle of inclination and viscosity parameter has a proportional increase in the pressure rise. Also, an increase in the porosity causes a significant reduction in the pressure rise.

Boundary Layer Flow through Darcy–Brinkman Porous Medium in the Presence of Slip Effects and Porous Dissipation

This paper aims to examine the Darcy–Brinkman flow over a stretching sheet in the presence of frictional heating and porous dissipation. The governing equations are modeled and simplified under boundary layer approximations, which are then transformed into system of self-similar equations using appropriate transformations. The resulting system of nonlinear equations was solved numerically under velocity and thermal slip conditions, by fourth-order Runge–Kutta method and built-in routine bvp4c in Matlab. Under special conditions, the obtained results were compared with the results available in the literature. An excellent agreement was observed. The variation of parameters was studied for different flow quantities of interest and results are presented in the form of tables and graphs.

Nano Fluid Flow Analysis in the Presence of Slip Effects and Wall Properties by Means of Contraction and Expansion**Supported by the project from HEC (SRGP) (No:21-1712/SRGP/R&D/HEC/2017)

The present article is a study of mixed convective peristaltic flow of Cu-blood nanofluid confined in a non-uniform tube along with the velocity slip conditions and wall properties. Endoscopic or catheterized special effects are also taken into description. Upon utilization of the large wavelength and small reynolds number approximation, the non-dimensional governing differential equation took a more simplified form, which is then solved for the exact solutions. Afterwards, these outcomes are offered graphically and are debated in detail. Velocity profile for pure blood as well as Cu-blood and no-slip and slip effects are also discussed separately. Streamlines pattern is also discussed for different physical parameters.

Computational analysis for velocity slip and diffusion species with carbon nanotubes

This article addresses a computational study for carbon nanotubes with diffusion species. Mathematical analysis and modeling are formulated in the presence of slip effect, Darcy porous medium and chemical species. Diffusion coefficients are accounted as equal amount. Optimal Homotopy Analysis Method (OHAM) is implemented in taking care for convergence control parameters. Residual errors and its graphs are plotted for CNTs nanofluids. The current data is compared with the previous published work. The results are found in favorable agreement. Physically interesting parameters are highlighted. The velocity is dominated for MWCNT than SWCNT. The velocity profile increases for power index when m>1 while opposite trend is observed for power index when m<1. Permeability parameter and volume fraction reduce the skin friction coefficient and reverse trend is noticed for slip parameter and wall thickness parameter. Opposite behavior is noticed for concentration profile at surface for homogenous-heterogeneous reactions parameters.

EFFECT OF POLYETHYLENE MOLECULAR MASS CHARACTERISTICS ON SLIP EFFECT

The rheological properties of polyethylene with different molecular weight characteristics were studied. Difference of molecular weight characteristics was found on the basis of melt flow index, and slip effect in the molten polyethylene flow was studied. The presence of slip effect is found in case of flowing polyethylene with a higher molecular weight in contrast to polyethylene with lower molecular weight at different temperatures. Changes of the slip effect parameters upon mixing polyethylenes with very much different molecular weight characteristics were studied.

Inspiration of slip effects on electromagnetohydrodynamics (EMHD) nanofluid flow through a horizontal Riga plate

The boundary layer flow of nanofluid that is electrically conducting over a Riga plate is considered. The Riga plate is an electromagnetic actuator which comprises a spanwise adjusted cluster of substituting terminal and lasting magnets mounted on a plane surface. The numerical model fuses the Brownian motion and the thermophoresis impacts because of the nanofluid and the Grinberg term for the wall parallel Lorentz force due to the Riga plate in the presence of slip effects. The numerical solution of the problem is presented using the shooting method. The novelties of all the physical parameters such as modified Hartmann number, Richardson number, nanoparticle concentration flux parameter, Prandtl number, Lewis number, thermophoresis parameter, Brownian motion parameter and slip parameter are demonstrated graphically. Numerical values of reduced Nusselt number, Sherwood number are discussed in detail.

Effect of Couple Stress Fluid Flow on Magnetohydrodynamic Peristaltic Blood Flow with Porous Medium through Inclined Channel in the Presence of Slip Effect - Blood Flow Model

Effect of couple stress fluid flow on magnetohydrodynamic peristaltic blood flow with porous medium trough inclined channel in the presence of slip effect-Blood flow study have been studied under the assumption of long wavelength approximations. The expressions of the axial velocity, transverse velocity, pressure gradient, volume flow rate, average volume flow rate, pressure rise and shear stress are obtained and discussed through graphs. It is noted that the axial velocity increases with increase in M, S and α and deceases with increase in D and β and the transverse velocity increases with increase in D and S and decreases with increase in M, β and α in the entire flow field. We notice the pressure gradient is maximum at x = 0.5.

Effect of Couple Stress Fluid Flow on Magnetohydrodynamic Peristaltic Blood Flow with Porous Medium through Inclined Channel in the Presence of Slip Effect - Blood Flow Model

Effect of Couple Stress Fluid Flow on Magnetohydrodynamic Peristaltic Blood Flow with Porous Medium through Inclined Channel in the Presence of Slip Effect - Blood Flow Model

Flow of a viscous fluid in a closed cavity in the presence of slip effects

Slip at the wall is observed in the flow of non-Newtonian fluids [1–4] and rarefied gases [5]. The most complete information on the phenomenon is obtained in capillary viscosimetry. For small radii of the capillaries and in porous media the slip effect is manifested even for Newtonian fluids (water, kerosene, for example) [6]. Experiments [2, 4] show that the influence of the entrance section can be ignored if the length of the capillary exceeds its radius by about 100 times. For the measurement of the rheological characteristics of high-viscosity fluids the use of long capillaries is difficult, and it is necessary to calculate the two-dimensional flow at the entrance section with allowance for slip. The need for such calculations also arises, for example, when one is choosing the optimal parameters of the screw devices employed in the processing of polymers [7]. Two-dimensional flows of a viscous incompressible fluid are frequently calculated with the flow function ψ and vorticity ϕ=− Δψ used as variables [8–14]. The expressions for the vorticity on the boundary are usually obtained from the viscous no-slip condition [8, 9]. In the present paper, expressions are obtained for the vorticity on a wall in the presence of slip. The obtained expressions are used to solve a test problem on the flow of a viscous incompressible fluid in a cavity.