Influence Of Slip Boundary Condition Research Articles

Influence of Slip Boundary Conditions on Jeffrey Fluid Flow in Tapered Conduit with Hall Current and Soret–Dufour Effects

AbstractThe present work examines the computational analysis and mathematical modeling of peristaltic blood flow in a tapered channel, taking into account slip boundary conditions, Hall current, and Soret–Dufour forces. By neglecting the wave number and employing a long‐wavelength approximation to analyze the fluid model, the investigation was conducted within the framework of a low Reynolds number regime. The study reveals that the values of the Soret number, Dufour number, Prandtl number, and Schmidt number exhibit an upward trend as the fluid temperature rises. In contrast, a rise in the thermal slip parameter causes the fluid temperature to fall. It has been shown that when the mass slip parameter increases, the fluid's concentration rises. The skin friction coefficient rises within the range of x = 0.55 to x = 1 as the velocity, concentration slip parameter, Soret number, and Dufour number increase. Conversely, the skin friction coefficient decreases as the thermal slip parameter increases. The selected characteristics exhibit realism since they find use in many fields such as medical biology, biomechanics, heat exchangers, gas turbines, and several other domains.

Inclined MHD Effects in Tapered Asymmetric Porous Channel with Peristalsis: Applications in Biomedicine

This paper emphasized an inclined magnetohydrodynamics (MHD) effects in tapered asymmetric porous channel with peristalsis in the presence of slip boundary conditions. Here we considered the two-dimensional channel with a porous medium. The fundamental assumptions of long wavelength and low Reynolds number are applied in the relevant nonlinear equations for momentum, heat, and mass transfer as part of mathematical modeling. The equations subjected to slip boundary conditions have been solved numerically by the Mathematica software. Various essential physical characteristics of velocity, temperature, concentration, and heat transfer rate are captured graphically in the end. The velocity profile is found parabolic for various involved parameters. It is observed that the embedded parameters behave in the exact opposite manner when compared with temperature and concentration distributions. The sinusoidal behavior of the heat transfer rate is also displayed. The unique aspect of this effort is specifically to relate the Joule heating, Darcy resistance, and inclined magnetic field effects in peristaltic flow for a non-Newtonian Jeffrey fluid in an asymmetric tapered channel under the influence of slip boundary conditions. Such preferences have a wide range of applications in engineering, biology, and industry. The outcomes of the presented work are also proficient in the medical field for the treatment of cancer using MHD. The MHD also aids in controlling blood pressure during systolic and diastolic pressure conditions by regulating the blood flow stream.

Development and theoretical analysis of slippery walls flow of third-grade fluid through the convergent symmetric channel

The present investigation is a study of third-grade fluid muddled with tiny-sized round-shaped hafnium particles drifting through a convergent geometry under the influence of slip boundary conditions. The impact of electro-osmotic is also examined in this investigation. The Debye Hückel linearization is used to investigate the current problem. Fluid and particulate phases are illustrated in convergent geometry having momentous utilizations in industry and different strolls of science. The problem is modeled in terms of nonlinear complex differential equations by using the fluid and particle phase models. The normalized quantities are used to convert the dimensional equations into dimensionless form and the perturbation method is selected to obtain the solution in analytical form. The effects of pertinent parameters on each type of flow are also presented graphically. Promotion in the velocity profile is observed for the volumetric flow parameter. The slip parameter boost motion of the fluid particle inside the channel. The current study can be utilized in the chemical industry, reservoir engineering, and microfabrication technique in which mass exchanges and electro-osmotic energy play a vital role.

Analysis of textured journal bearing with slip boundary condition and pseudoplastic lubricants

The present study investigates the combined influence of slip boundary condition and non-Newtonian lubricants on the tribological performance of hydrodynamic textured journal bearing. To accurately predict the effect of air/vapor bubble formation in diverging zone of the slip-texture bearing, the modified Reynolds equation with considering the Elrod cavitation model has been solved. In addition, the energy equation under adiabatic condition has been also solved for including the loss of viscosity with the temperature rise of lubricant. It has been observed that slip-texture bearings with change in rheology of lubricant from Newtonian to Pseudoplastic shows significant improvement in the maximum pressure, the average rise in temperature, and lubricant-bearing friction-force. Further findings of the study indicate that the combined effect of slip boundary condition and micro-texture with suitable selection of lubricant rheology is beneficial in increasing the stability of hydrodynamic lubricant film in the journal bearings.

Numerical Study of Nanoparticle Deposition in a Gaseous Microchannel under the Influence of Various Forces

Nanoparticle deposition in microchannel devices inducing contaminant clogging is a serious barrier to the application of micro-electro-mechanical systems (MEMS). For micro-scale gas flow fields with a high Knudsen number (Kn) in the microchannel, gas rarefaction and velocity slip cannot be ignored. Furthermore, the mechanism of nanoparticle transport and deposition in the microchannel is extremely complex. In this study, the compressible gas model and a second-order slip boundary condition have been applied to the Burnett equations to solve the flow field issue in a microchannel. Drag, Brownian, and thermophoretic forces are concerned in the motion equations of particles. A series of numerical simulations for various particle sizes, flow rates, and temperature gradients have been performed. Some important features such as reasons, efficiencies, and locations of particle deposition have been explored. The results indicate that the particle deposition efficiency varies more or less under the actions of forces such as Brownian force, thermophoretic force, and drag force. Nevertheless, different forces lead to different particle motions and deposition processes. Brownian or thermophoretic force causes particles to move closer to the wall or further away from it. The drag force influence of slip boundary conditions and gas rarefaction changes the particles’ residential time in the channel. In order to find a way to decrease particle deposition on the microchannel surface, the deposition locations of different sizes of particles have been analyzed in detail under the action of thermophoretic force.

Peristaltic flow of Jeffery fluid with Heat and Mass Transfer Through an Inclined Asymmetric Tapered Channel under an Influence of Slip Boundary Conditions

The present investigation highlighted the peristaltic flow of Jeffery fluid with heat and mass transfer through an inclined asymmetric tapered channel under an influence of slip boundary conditions. Thermal radiation, rotation, hall current and porous medium are also taken in to the consideration. The momentum, temperature and concentration equations have been linearized under long wavelength and low-Reynolds number assumptions and analytical solutions for the flow variables have been derived. Expressions for the velocity, pressure gradient, pressure rise, temperature and concentration have been obtained. The results are displayed and discussed through graphs. Mathematica software is used to find out numerical results.

Newtonian and viscoelastic fluid flows through an abrupt 1:4 expansion with slip boundary conditions

In this work, we present a systematic numerical investigation of the 1:4 planar expansion creeping flow under the influence of slip boundary conditions for Newtonian and viscoelastic fluids, the latter modeled by the simplified Phan–Thien–Tanner constitutive model. The linear and nonlinear Navier slip laws were considered with the dimensionless slip coefficient kl* varying in the range 0, 4500 and the slip exponents m = 0.5, 1, and 2. The simulations were carried out for a low Reynolds number, Re = 0.001, and for Deborah numbers (De) between 0 and 100. Convergence could not be achieved for higher values of the Deborah number and large values of the slip coefficient due to the large stress gradients near the singularity point (reentrant corner). The results obtained allow us to conclude that for all De, the increase in slip velocity leads to vortex suppression. The flow characteristics are described in detail for low values of the Deborah number, De ≤ 5, while for higher De the main features are only shown for specific values of the slip coefficient. These results find application in polymer processing, where the use of lubricants that migrate to the wall is common, which promotes slip.

Heat and Mass Transfer of Free Convection Flow Over a Vertical Plate with Chemical Reaction Under Wall–Slip Effect

This research work deals with the influence of heat and mass transfer on the natural convection flow over an infinite vertical plate with constant concentration and ramped wall temperature under the influence of slip boundary condition. The effects of chemical molecular diffusivity along with chemical and heat transfer processes have been studied. Solutions for the fluid velocity, temperature and concentration are achieved in closed forms by applying Laplace transform technique. The influence of embedded physical parameters on the flow characteristics has been analyzed graphically.

Influence of Slip Boundary Condition on Oil Film Flow Between Piston and Cylinder

Influence of Slip Boundary Condition on Oil Film Flow Between Piston and Cylinder

The Influence of Slip Boundary Condition on Casson Nanofluid Flow over a Stretching Sheet in the Presence of Viscous Dissipation and Chemical Reaction

The impacts of multiple slips with viscous dissipation on the boundary layer flow and heat transfer of a non-Newtonian nanofluid over a stretching surface have been investigated numerically. The Casson fluid model is applied to characterize the non-Newtonian fluid behavior. Physical mechanisms responsible for Brownian motion and thermophoresis with chemical reaction are accounted for in the model. The governing nonlinear boundary layer equations through appropriate transformations are reduced into a set of nonlinear ordinary differential equations, which are solved numerically using a shooting method with fourth-order Runge-Kutta integration scheme. Comparisons of the numerical method with the existing results in the literature are made and an excellent agreement is obtained. The heat transfer rate is enhanced with generative chemical reaction and concentration slip parameter, whereas the reverse trend is observed with destructive chemical reaction and thermal slip parameter. It is also noticed that the mass transfer rate is boosted with destructive chemical reaction and thermal slip parameter. Further, the opposite influence is found with generative chemical reaction and concentration slip parameter.

Effect of Homogeneous and Heterogeneous Chemical Reactions on Peristaltic Transport of a Jeffrey Fluid through a Porous Medium with Slip Condition

In this paper, the dispersion of solute matter in a Jeffrey fluid flow through a porous medium in a peristaltic channel has been investigated under the influence of slip boundary conditions. Long wavelength approximation and Taylor's limiting condition are used to obtain the average effective dispersion coefficient in both the cases of homogeneous and heterogeneous chemical reactions. The effects of various pertinent parameters on the effective dispersion coefficient are discussed. Average effective dispersion coefficient increases with amplitude ratio. That is, more dispersion in the presence of peristalsis. Further, the average effective dispersion coefficient increases with the permeability parameter and the slip parameter; but decreases with the Jeffrey number, homogeneous / heterogeneous chemical reaction rate parameter.

Slip flows of Newtonian and viscoelastic fluids in a 4:1 contraction

This work presents a numerical study of the 4:1 planar contraction flow of a viscoelastic fluid described by the simplified Phan-Thien–Tanner model under the influence of slip boundary conditions at the channel walls. The linear Navier slip law was considered with the dimensionless slip coefficient varying in the range [0;4500]. The simulations were carried out for a small constant Reynolds number of 0.04 and Deborah numbers (De) varying between 0 and 5. Convergence could not be achieved for higher values of the Deborah number, especially for large values of the slip coefficient, due to the large stress gradients near the singularity of the reentrant corner.Increasing the slip coefficient leads to the formation of two vortices, a corner and a lip vortex. The lip vortex grows with increasing slip until it absorbs the corner vortex, creating a single large vortex that continues to increase in size and intensity. In the range De=3–5 no lip vortex was formed. The flow is characterized in detail for De=1 as function of the slip coefficient, while for the remaining De only the main features are shown for specific values of the slip coefficient.

Influence of heat generation and heat flux on peristaltic flow with interacting nanoparticles

In the current study, we have examined the peristaltic flow of three different nanoparticles with water as base fluid under the influence of slip boundary conditions through a vertical asymmetric porous channel in the presence of MHD. The selected nanoparticles are titanium dioxide ( TiO2 , copper oxide (CuO) and silicon dioxide ( SiO2 . The Brownian motion shows that the effective conductivity increases to result in a lower temperature gradient for a given heat flux. To examine these transport phenomena thoroughly, we also consider the thermal conductivity model of Brownian motion for nanofluids, this increases the effect of the particle size, particle volume fraction and temperature dependence. The mathematical formulation is presented. Exact solutions are obtained from the resulting equations. The obtained expressions for pressure gradient, temperature and velocity profile are described through graphs for the various relevant parameters. The streamlines are drawn for some physical quantities to discuss the trapping phenomenon.

Development Length in Planar Channel Flows of Newtonian Fluids Under the Influence of Wall Slip

This technical brief presents a numerical study regarding the required development length (L=Lfd/H) to reach fully developed flow conditions at the entrance of a planar channel for Newtonian fluids under the influence of slip boundary conditions. The linear Navier slip law is used with the dimensionless slip coefficient k¯l=kl(μ/H), varying in the range 0<k¯l≤1. The simulations were carried out for low Reynolds number flows in the range 0<Re≤100, making use of a rigorous mesh refinement with an accuracy error below 1%. The development length is found to be a nonmonotonic function of the slip velocity coefficient, increasing up to k¯l≈0.1-0.4 (depending on Re) and decreasing for higher k¯l. We present a new nonlinear relationship between L, Re, and k¯l that can accurately predict the development length for Newtonian fluid flows with slip velocity at the wall for Re of up to 100 and k¯l up to 1.

PERISTALTIC FLOW OF COUPLE-STRESS CONDUCTING FLUIDS THROUGH A POROUS CHANNEL: APPLICATIONS TO BLOOD FLOW IN THE MICRO-CIRCULATORY SYSTEM

The present investigation is devoted to study a theoretical investigation of the peristaltic flow of a couple-stress conducting fluids in a porous channel under the influence of slip boundary condition. This study is applicable to the physiological flow of blood in the micro-circulatory system, by taking account of the particle size effect. The expressions for axial velocity, pressure gradient, stream function, frictional force and mechanical efficiency are obtained under the small Reynolds number and the large wavelength approximations. Effects of different physical parameters reflecting permeability parameter, couple-stress parameter, Hartmann number as well as amplitude ratio on pumping characteristics, frictional force, mechanical efficiency and trapping of peristaltic flow pattern are studied. The computational and numerical results are presented in graphical form. On the basis of our discussion, it is concluded that pressure reduces by increasing the magnitude of couple-stress parameter, permeability parameter, slip parameter, whereas it enhances by increasing the magnitude of magnetic field and amplitude ratio.

The Influence of Slip Boundary Conditions on Peristaltic Pumping in a Rectangular Channel

The flow of an incompressible fluid is modeled in a channel of a rectangular cross section with two symmetric peristaltic waves propagating on the top and bottom. A low Reynolds number and a long wavelength are assumed. The effect on pumping of the inclusion of slip boundary conditions on the side walls is investigated.

A numerical study of the influence of slip boundary condition on rotating flow

A numerical solution is obtained for the steady flow of an electrically conducting non-Newtonian incompressible fluid past a plate. The flow is analysed under condition where the no-slip assumption between the plate and the fluid is no longer valid. The fluid under consideration obeys the rheological equations of state due to a third-grade fluid. The fluid is conducting in the presence of a uniform magnetic field under a small magnetic Reynolds number. The solution of the nonlinear equations of motion is obtained using MATLAB®. The effects of the slip, third-grade parameter and magnetic field on the velocity distribution are presented graphically and discussed.

The destabilizing effect of boundary slip on Bénard convection

AbstractWe investigate the influence of slip boundary conditions on the onset of Bénard convection in an infinite fluid layer. It is shown that the critical Rayleigh number is a decreasing function of the slip length, and therefore boundary slip is seen to have a destabilizing effect. Chebyshev‐tau and compound matrix formulations for solving the eigenvalue problem are presented. Copyright © 2005 John Wiley & Sons, Ltd.

A note on the stability of slip channel flows

We consider the influence of slip boundary conditions on the modal and nonmodal stability of pressure-driven channel flows. In accordance with previous results by Gersting [“Hydrodynamic stability of plane porous slip flow,” Phys. Fluids 17, 2126 (1974)] but in contradiction with the recent investigation of Chu [“Instability of Navier slip flow of liquids,” C. R. Mec. 332, 895 (2004)], we show that the slip increases significantly the value of the critical Reynolds number for linear instability. The nonmodal stability analysis, however, reveals that slip has a very weak influence on the maximum transient energy growth of perturbations at subcritical Reynolds numbers. Slip boundary conditions are therefore not likely to have a significant effect on the transition to turbulence in channel flows.

An experimental investigation of the dynamic contact angle in liquid-liquid systems

We report measurements of dynamic contact angles performed during the displacement of silicone oil/air and silicone oil/glycerin interfaces in capillary glass tubes. The data obtained for the liquid/air interfaces are in good agreement with other experiments performed by other authors. They also agree with the so-called Hoffman-Tanner law, and with theoretical estimates done by Cox. On the other hand, results obtained with liquid/liquid interfaces show a systematic increase of the dynamic angle compared to theoretical predictions. There are two possible explanations of this fact, which is also reported by other authors. One of them is related to the additional energy dissipation occurring when the contact line moves on a heterogeneous surface. The other one is based on molecular dynamics simulations by Robbins and Thompson, and relies on the influence of slip boundary conditions on the dynamic angle.