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1.
The problem of peristaltic flow of a Newtonian fluid with heat transfer in a vertical asymmetric channel through porous medium is studied under long-wavelength and low-Reynolds number assumptions. The flow is examined in a wave frame of reference moving with the velocity of the wave. The channel asymmetry is produced by choosing the peristaltic wave train on the walls to have different amplitudes and phase. The analytical solution has been obtained in the form of temperature from which an axial velocity, stream function and pressure gradient have been derived. The effects of permeability parameter, Grashof number, heat source/sink parameter, phase difference, varying channel width and wave amplitudes on the pressure gradient, velocity, pressure drop, the phenomenon of trapping and shear stress are discussed numerically and explained graphically.  相似文献   

2.
The effect of a third-order fluid on the peristaltic transport in an asymmetric channel is studied. The wavelength of the peristaltic waves is assumed to be large compared to the varying channel width, whereas the wave amplitudes need not be small compared to the varying channel width. The channel asymmetry is produced by choosing the peristaltic wave train on the walls to have different amplitudes and phase. The flow is investigated in a wave frame of reference moving with velocity of the wave. The effects of Deborah number, phase difference, varying channel width and wave amplitudes on the pumping characteristics, streamline pattern and trapping phenomena are investigated. It is observed that the trapping regions increase as the channel becomes more and more symmetric and the trapped bolus volume decreases for increasing Deborah number, phase difference and varying channel width whereas it increases for increasing flow rate and wave amplitudes. Furthermore, the obtained results could also have applications to a range of peristaltic flows for a variety of non-Newtonian fluids such as aqueous solutions of high-molecular weight polyethylene oxide and polyacrylamide.  相似文献   

3.
The effect of variable viscosity on the peristaltic flow of a Newtonian fluid in an asymmetric channel has been discussed. Asymmetry in the flow is induced due to travelling waves of different phase and amplitude which propagate along the channel walls. A long wavelength approximation is used in the flow analysis. Closed form analytic solutions for velocity components and longitudinal pressure gradient are obtained. The study also shows that, in addition to the effect of mean flow parameter, the wave amplitude also effect the peristaltic flow. This effect is noticeable in the pressure rise and frictional forces per wavelength through numerical integration.  相似文献   

4.
This paper describes the fluid mechanics effects of mixed convective heat and mass transfer in an asymmetric channel with peristalsis. The flow is examined in a wave frame of reference moving with the velocity of the wave. The channel asymmetry is produced by choosing the peristaltic wave train on the walls to have different amplitudes and phase. The momentum, energy and concentration equations have been linearized under long wavelength approximation. The analytical solutions for temperature, concentration, velocity and stream function are obtained. The effects of various parameters such as local temperature Grashof number, local mass Grashof number and geometrical parameters on flow variables have been discussed numerically and explained graphically.  相似文献   

5.
The present paper investigates phenomena brought about into the classic peristaltic mechanism by inclusion of non-Newtonian effects through a porous space in a channel. The peristaltic motion of a second-order fluid through a porous medium was studied for the case of a planar channel with harmonically undulating extensible walls. The system of the governing nonlinear PDE is solved by using the perturbation method to second-order in dimensionless wavenumber. The analytic solution has been obtained in the form of a stream function from which the axial pressure gradient has been derived. The flow is investigated in a wave frame of reference moving with velocity of the wave. Numerical calculations are carried out for the pressure rise and frictional force. The features of the flow characteristics are analyzed by plotting graphs and discussed in detail.  相似文献   

6.
The peristaltic flow of a Williamson fluid in asymmetric channels with permeable walls is investigated. The channel asymmetry is produced by choosing a peristaltic wave train on the wall with different amplitudes and phases. The solutions for stream function, axial velocity and pressure gradient are obtained for small Weissenberg number, We, via a perturbation expansion about We, while an exact solution method is discussed for large values of We. The exact solutions become singular as We tends to zero; hence the separate perturbation solutions are essential. Also, numerical results are obtained using the perturbation technique for the pumping and trapping phenomena, and these are used to bring out the qualitative features of the solutions. It is noted that the size of the trapped bolus decreases and its symmetry disappears for large values of the permeability parameter. The effects of various wave forms (namely, sinusoidal, triangular, square and trapezoidal) on the fluid flow are discussed.  相似文献   

7.
The interaction of purely periodic mean flow with a peristaltic induced flow is investigated within the framework of a two-dimensional analogue. The mathematical model considers a viscous incompressible fluid under the effect of transverse magnetic field, taking into account the effect of Hall currents for a magneto-fluid with suspended particles between infinite parallel walls on which a sinusoidal traveling wave is imposed. A perturbation solution to the complete set of Navier-Stokes equations is found for the case in which the frequency of the traveling wave and that of the imposed pressure gradient are equal. The ratio of the traveling wave amplitude to channel width is assumed to be small. For this case a first order steady flow is found to exist, as contrasted to a second order effect in the absence of the imposed periodic pressure gradient. The effect of Hall parameter, Hartmann number and the various parameters included in the problem are discussed numerically.  相似文献   

8.
This paper concern with the peristaltic transport of MHD Newtonian fluid in a symmetric, two dimensional channel with variable viscosity under the influence of heat transfer analysis. For the formulation of the problem long wave length and low Reynold number assumption is taken into account. An exact solution is presented for the temperature field. The velocity field for the model of interest is solved by Adomian decomposition method. Numerical illustrations that show the physical effects and the pertinent features are investigated at the end of the paper.  相似文献   

9.
The elastic effect of the flexible walls is analyzed on the peristaltic motion of Maxwell fluid in a channel with heat transfer. An incompressible and magnetohydrodynamic (MHD) fluid fills the porous space. The series solution of the modeled problem is derived by considering small wave number. The influence of pertinent parameters is shown and discussed with the help of graphs. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010  相似文献   

10.
The present study extends the two-dimensional analysis of peristaltic motion to include a compliant wall. The fluid-solid interaction problem is investigated by considering equations of motion of both the fluid and the deformable boundaries. The driving mechanism of the muscle is represented by assuming the channel walls to be compliant. A perturbation solution of the stream function for zeroth, first and second order in a small amplitude ratio is obtained. The phenomenon of the “mean flow reversal” is found to exist both at the center and at the boundaries of the channel. The effect of wall damping, wall elastance and wall tension on the mean axial velocity and reversal flow has been investigated. The numerical results show that the possibility of flow reversal increases by increasing the wall damping and decreases by increasing the wall elastance and wall tension.  相似文献   

11.
The present study investigates the channel flow of a third order fluid. The fluid is electrically conducting in the presence of a magnetic field applied transversely to the porous walls of a channel. Expression for velocity is developed by an analytic method, namely the homotopy analysis method (HAM). Convergence of the obtained solution is properly checked. The feature of the analytic solution as function of the physical parameters of the problem are discussed with the help of graphs. It is observed that unlike the flow of second grade fluid, the obtained solution for a third order fluid is non-similar. Also, the behavior of Hartmann number on the velocity is different to that of the Reynold's number.  相似文献   

12.
The peristaltic flow of a Maxwell fluid in an asymmetric channel is studied. Asymmetry in the flow is induced by taking peristaltic wave train of different amplitudes and phase. The viscoelasticity of the fluid is induced in the momentum equation. An analytic solution is obtained through a series of the wave number. The leading velocity term denotes the Newtonian result. The first and second order terms are the viscoelastic contribution to the flow. Expressions for stream function and longitudinal pressure gradient are obtained analytically. Numerical computations have been performed for the pressure rise per wavelength and discussed.  相似文献   

13.
This paper presents an analytical study of the MHD flow of a micropolar fluid through a porous medium induced by sinusoidal peristaltic waves traveling down the channel walls. Low Reynolds number and long wavelength approximations are applied to solve the non-linear problem in the closed form and expressions for axial velocity, pressure rise per wavelength, mechanical efficiency and stream function are obtained. The impacts of pertinent parameters on the aforementioned quantities are examined by plotting graphs on the basis of computational results. It is found that the pumping improves with Hartman number but degrades with permeability of the porous medium.  相似文献   

14.
This article discusses the effect of heat transfer on the peristaltic flow of a Newtonian fluid through a porous space in a vertical asymmetric channel. Long wavelength approximation is used to linearize the governing equations. The system of the governing nonlinear PDE is solved by using the perturbation method. The solutions are obtained for the velocity and the temperature fields. The flow is investigated in a wave frame of reference moving with velocity of the wave. Numerical calculations are carried out for the pressure rise, frictional forces, and the features of the flow and temperature characteristics are analyzed by plotting graphs and discussed in detail. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010  相似文献   

15.
Of concern in the paper is a generalized theoretical study of the non-Newtonian characteristics of peristaltic flow of blood through micro-vessels, e.g. arterioles. The vessel is considered to be of variable cross-section and blood to be a Herschel–Bulkley type of fluid. The progressive wave front of the peristaltic flow is supposed sinusoidal/straight section dominated (SSD) (expansion/contraction type); Reynolds number is considered to be small with reference to blood flow in the micro-circulatory system. The equations that govern the non-Newtonian peristaltic flow of blood are considered to be non-linear. The objective of the study has been to examine the effect of amplitude ratio, mean pressure gradient, yield stress and the power law index on the velocity distribution, wall shear stress, streamline pattern and trapping. It is observed that the numerical estimates for the aforesaid quantities in the case of peristaltic transport of blood in a channel are much different from those for flow in an axisymmetric vessel of circular cross-section. The study further shows that peristaltic pumping, flow velocity and wall shear stress are significantly altered due to the non-uniformity of the cross-sectional radius of blood vessels of the micro-circulatory system. Moreover, the magnitude of the amplitude ratio and the value of the fluid index are important parameters that affect the flow behaviour. Novel features of SSD wave propagation that affect the flow behaviour of blood have also been discussed.  相似文献   

16.
Slip and heat transfer effects on the peristaltic flow in an asymmetric channel have been examined in this paper. The closed form solutions of momentum and energy equations are obtained for long wavelength and low Reynolds number approximations. Pumping and trapping phenomena are discussed by numerical integration. The variations of velocity and thermal slip parameters are particularly observed. Comparison of different wave forms for symmetric case is presented.  相似文献   

17.
Effects of complaint wall properties on the flow of a Newtonian viscous compressible fluid has been studied when the wave propagating (surface acoustic wave, SAW) along the walls in a confined parallel‐plane microchannel is conducted by considering the slip velocity. A perturbation technique has been employed to analyze the problem where the amplitude ratio (wave amplitude/half width of channel) is chosen as a parameter. In the second order approximation, the net axial velocity is calculated for various values of the fluid parameters and wall parameters. The phenomenon of the “mean flow reversal” is found to exist both at the center and at the boundaries of the channel. The effect of damping force, wall tension, and compressibility parameter on the mean axial velocity and reversal flow has been investigated, also the critical values of the tension are calculated for the pertinent flow parameters. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 621–636, 2011 Keywords:  相似文献   

18.
This article describes the effects of heat and mass transfer on the magnetohydrodynamic (MHD) peristaltic flow in a planar channel with compliant walls. An incompressible Maxwell fluid occupies a porous space. The mathematical formulation is based upon the modified Darcy’s law. The analytic treatment of the solution is given by choosing a small wave number. The expressions of stream function, temperature distribution, concentration field and heat coefficient are constructed. The variations of several interesting parameters are discussed by sketching plots.  相似文献   

19.
This investigation deals with the peristaltic motion of a Carreau fluid in a planar channel by employing long wavelength approximation. Five wave forms are chosen. Explicit solutions of longitudinal velocity and pressure gradient are derived. The pumping and trapping phenomena are properly examined. Comparison is made for the flow characteristics of the various selected wave forms. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010  相似文献   

20.
The present study investigates the effects of heat and mass transfer on peristaltic transport in a porous space with compliant walls. The fluid is electrically conducting in the presence of a uniform magnetic field. Analytic solution is carried out under long-wavelength and low-Reynolds number approximations. The expressions for stream function, temperature, concentration and heat transfer coefficient are obtained. Numerical results are graphically discussed for various values of physical parameters of interest.  相似文献   

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