Jeffrey流体流过有限长圆柱管时磁流体动力学的蠕动流

研究Jeffrey流体流过有限长管道时的蠕动流.在外加磁场作用时,流体呈导电性.分析是在长波长和低Reynolds数近似假设下完成.得到了压力梯度、体积流量、平均体积流量和局部壁面剪应力的表达式.研究了松弛时间、延迟时间和Hartman数,对压力、局部壁面剪应力以及蠕动泵机械效率的影响.还研究了回流现象,调查了沿管道壁波数非整倍数时的传播情况,研究有限长管道传播的内在特性.     

Effects of rotation and magnetic field on the nonlinear peristaltic flow of a second-order fluid in an asymmetric channel through a porous medium

In this paper, the effects of both rotation and magnetic field of the peristaltic transport of a second-order fluid through a porous medium in a channel are studied analytically and computed numerically. The material is represented by the constitutive equations for a second-order fluid. Closed-form solutions under the consideration of long wavelength and low Reynolds number is presented. The analytical expressions for the pressure gradient, pressure rise, friction force, stream function, shear stress, and velocity are obtained in the physical domain. The effects of the non-dimensional wave amplitude, porosity, magnetic field, rotation, and the dimensionless time-mean flow in the wave frame are analyzed theoretically and computed numerically. Numerical results are given and illustrated graphically in each case considered. Comparison was made with the results obtained in the presence and absence of rotation, magnetic field, and porosity. The results indicate that the effects of the non-dimensional wave amplitude, porosity, magnetic field, rotation, and the dimensionless time-mean flow are very pronounced in the phenomena.     

Peristaltic Flow of Couple Stress Fluid in a Non-Uniform Rectangular Duct Having Compliant Walls

The present study investigates the peristaltic flow of couple stress fluid in a non-uniform rectangular duct with compliant walls.Mathematical modeling is based upon the laws of mass and linear momentum.Analytic solutions are carried out by the eigen function expansion method under long-wavelength and low-Reynolds number approximations.The features of the flow characteristics are analyzed by plotting the graphs of various values of physical parameters of interest.Trapping bolus scheme is also presented through streamlines.     

Numerical prediction of flow in a model of a (potential) soft acting peristaltic blood pump

This paper presents a numerical study of the flow field in a novel ‘soft’ acting peristaltic pump. The pump has potential applications wherever pumping of biological or sensitive fluids with reduced damage is required. The application of the device presented is as a blood pump. The model of the pump comprises a cylindrical tube that forms three chambers. The walls of these chambers move radially as a function of time. The pumping action is initiated by applying phased movement between the chambers. The flow is treated as laminar, unsteady, incompressible, Newtonian, and with a moving boundary. The governing equations are solved using a finite element method (FEM). An operating speed of 60 cycle min⁻¹ has been chosen. The results show that a periodic solution can be achieved after four cycles. The velocity field, streamline and shear stress are presented and discussed. The flow has generally a two‐way pulsatile nature, moving forwards and backwards. However, at the outlet, there is a net outflow over one cycle against a zero pressure head. Net flow linearly decreases to zero with increasing pressure head. Copyright © 2000 John Wiley & Sons, Ltd.     

Wall properties and heat transfer analysis of the peristaltic motion in a power‐law fluid

A mathematical analysis has been carried out to investigate the effect of elasticity of the flexible walls on the peristaltic flow of a power‐law fluid. The heat transfer analysis is further examined. Expressions of stream function, velocity, and temperature distributions are presented in closed form under long wavelength and low Reynolds number approximations. The effects of the various parameters entering into the mathematical analysis are sketched and discussed. Copyright © 2012 John Wiley & Sons, Ltd.     

Peristaltic transport and heat transfer of a MHD Newtonian fluid with variable viscosity

The influence of temperature‐dependent viscosity and magnetic field on the peristaltic flow of an incompressible, viscous Newtonian fluid is investigated. The governing equations are derived under the assumptions of long wavelength approximation. A regular perturbation expansion method is used to obtain the analytical solutions for the velocity and temperature fields. The expressions for the pressure rise, friction force and the relation between the flow rate and pressure gradient are obtain. In addition to analytical solutions, numerical results are also computed and compared with the analytical results with good agreement. The results are plotted for different values of variable viscosity parameter β, Hartmann number M, and amplitude ratio ?. It is found that the pressure rise decreases as the viscosity parameter β increases and it increases as the Hartmann number M increases. Finally, the maximum pressure rise (σ=0) increases as M increases and β decreases. Copyright © 2009 John Wiley & Sons, Ltd.     

Maxwell流体在有限长管道中作不稳定的蠕动传输:食道吞咽进程分析

解析地研究了有限长管道中Maxwell流体的不稳定蠕动传输.管壁受到不超过静止边界的收缩波作用.对无量纲形式的方程,应用长波长近似进行分析.导出了轴向速度和径向速度的表达式,评估了沿波长和管道长度方向的压力.讨论了回流现象,确定了回流极限区域.对食道中咀嚼食物(如面包、蛋白等)传输的数学公式给出了物理上的解释.可以看出,与Newton流体相比,Maxwell流体有利于在食道中的流动.与Takahashi等[Rheology,1999,27:169-172]的实验结果相符合.进一步揭示了松弛时间既不影响剪应力,也不影响回流极限.发现了压力的峰值,对整数值波列是相同的,而对非整数值波列是不同的.     

Numerical and analytical simulation of peristaltic flow of a Jeffrey-six constant fluid

This paper describes the Peristaltic flow of a Jeffrey-six constant fluid in an endoscope. The two-dimensional equation of Jeffrey-six constant fluid is simplified by making the assumptions of long wave length and low Reynolds number. The reduced momentum equations are solved with three methods, namely (i) Perturbation method, (ii) Homotopy analysis method, and (iii) shooting method. The comparison of the three solutions shows a very good agreement between the three results. The expressions for pressure rise and frictional forces per wave length have been also computed numerically. Finally, the pressure rise, frictional forces are plotted for different parameters of interest.     

Endoscopic Effects onPeristaltic Flow of a Nanofluid

In the present investigation we have studied the peristaltic flow of a nanofluid in an endoscope. The flow is investigated in a wave frame of reference moving with velocity of the wavec. Analytical solutions have been calculated using Homotopy perturbation method (HPM) for temperature and nanoparticle equation while exact solutions have been calculated for velocity and pressure gradient. Numerical integration have been used to obtain the graphical results for pressure rise and frictional forces. The effects of various emerging parameters are investigated for five different peristaltic waves.
Streamlines have been plotted at the end of the article.