共查询到20条相似文献,搜索用时 15 毫秒
1.
二阶流体通过径向延伸平面时滑移、黏性耗散、焦耳热对MHD流动的影响 总被引:1,自引:0,他引:1
研究了二阶导电的非Newton流体,在一个可径向放射状延伸,并伴有部分滑动表面上的流动及其热交换.部分滑移用一个无量纲的滑移因子控制,其取值范围从0(全黏着)到无穷大(全滑移).使用适当的相似变换,把待求的非线性偏微分方程转化为常微分方程.讨论了边界条件的不足,在无需增加任何边界条件下,使用有效的数值格式,求解所得到的微分方程.部分滑移、磁场交互参数以及二阶流体的参数对速度场和温度场的综合分析发现,滑移量的增加,流体的动力边界层和热边界层增厚.因为当滑移量的增加,允许更多的流体通过该平面,表面摩擦因数的数值下降,并在更高的滑移参数下,摩擦因数趋于0,即流体无黏性地通过.还研究了磁场对速度场和温度场的重要影响. 相似文献
2.
T. Hayat M. Asif Farooq T. Javed M. Sajid 《Nonlinear Analysis: Real World Applications》2009,10(2):745-755
This article looks at the slip effects on the flow and heat transfer of a third grade fluid past a porous plate. The resulting equations and boundary conditions are non-linear. The non-linear boundary condition is reduced into a linear one and a series solution of the problem is obtained using the homotopy analysis method (HAM). Variations of interesting parameters are seen on the velocity and temperature profiles. 相似文献
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Bikash Sahoo 《Communications in Nonlinear Science & Numerical Simulation》2009,14(3):811-826
The laminar flow and heat transfer of an incompressible, third grade, electrically conducting fluid impinging normal to a plane in the presence of a uniform magnetic field is investigated. The heat transfer analysis has been carried out for two heating processes, namely, (i) with prescribed surface temperature (PST-case) and (ii) prescribed surface heat flux (PHF-case). By means of the similarity transformation, the governing non-linear partial differential equations are reduced to a system of non-linear ordinary differential equations and are solved by a second-order numerical technique. Effects of various non-Newtonian fluid parameters, magnetic parameter, Prandtl number on the velocity and temperature fields have been investigated in detail and shown graphically. It is found that the velocity gradient at the wall decreases as the third grade fluid parameter increases. 相似文献
5.
Bikash Sahoo 《Communications in Nonlinear Science & Numerical Simulation》2009,14(7):2982-2998
The steady Von Kármán flow and heat transfer of an electrically conducting non-Newtonian fluid is extended to the case where the disk surface admits partial slip. The fluid is subjected to an external uniform magnetic field perpendicular to the plane of the disk. The constitutive equation of the non-Newtonian fluid is modeled by that for a Reiner–Rivlin fluid. The momentum equations give rise to highly non-linear boundary value problem. Numerical solutions for the governing non-linear equations are obtained over the entire range of the physical parameters. The effects of slip, magnetic parameter and non-Newtonian fluid characteristics on the velocity and temperature fields are discussed in detail and shown graphically. Emphasis has been laid to study the effects of viscous dissipation and Joule heating on the thermal boundary layer. It is interesting to find that the non-Newtonian cross-viscous parameter has an opposite effect to that of the slip and the magnetic parameter on the velocity and the temperature fields. 相似文献
6.
《Communications in Nonlinear Science & Numerical Simulation》2008,13(2):269-276
Radiation effects on natural convection heat transfer past an inclined semi-infinite surface is investigated using Lie group analysis. Symmetries found reduce the partial differential equations governing the fluid motion to a system of ordinary differential equations with appropriate boundary conditions. Numerical solution obtained using the fourth order Runge–Kutta scheme with shooting method shows that the thickness of the thermal boundary layer decreases and velocity increases with increasing Grashof number. Also it is observed that increasing the value of the radiation parameter increases both the temperature and velocity of the fluid. 相似文献
7.
The present study introduces a mathematical formulation for externally pressurized circular porous bearings. A porous layer is used to cover one of the bearing surfaces. An empirical boundary condition with a nonzero tangential velocity, which is known as the velocity slip at the interface, is incorporated into the analysis. The effect of pressure on lubricant viscosity is also considered. The mathematical model consists of two coupled partial differential equations; the first governs the pressure distribution in the film and the second governs the pressure distribution in the porous layer. A simultaneous numerical solution of these equations with the boundary conditions is presented. The effects of porous layer permeability parameter, lubricant viscosity parameter, recess radius, and film thickness on pressure distribution and load-carrying capacity are presented and discussed. 相似文献
8.
《Communications in Nonlinear Science & Numerical Simulation》2011,16(11):4284-4295
The steady flow and heat transfer arising due to the rotation of a non-Newtonian fluid at a larger distance from a stationary disk is extended to the case where the disk surface admits partial slip. The constitutive equation of the non-Newtonian fluid is modeled by that for a Reiner–Rivlin fluid. The fluid is subjected to an external uniform magnetic field perpendicular to the plane of the disk. The momentum equation gives rise to a highly nonlinear boundary value problem. Numerical solution of the governing nonlinear equations are obtained over the entire range of the physical parameters. The effects of slip, non-Newtonian fluid characteristics and the magnetic interaction parameter on the momentum boundary layer and thermal boundary layer are discussed in detail and shown graphically. It is observed that slip has prominent effects on the velocity and temperature fields. 相似文献
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给出了在一个特殊坐标系中三阶流体的二维定常运动方程组.该坐标系中由无粘流体的势流确定,即以环绕任意物体的非粘性流动的流线为Ф-坐标,速度势线为ψ-坐标,构成正交曲线坐标系.结果表明,边界层方程与浸没在流体中的物体的形状无关.第一次近似假定第二梯度项与粘性项和第三梯度项相比,可以忽略不计.第二梯度项的存在,将防碍第三梯度流相似解的比例变换的导出.利用李群方法计算了边界层方程的无穷小生成元.将边界层方程组变换为常微分方程组.利用Runge-Kutta法结合打靶技术求解了该非线性微分方程组的数值解. 相似文献
11.
Bikash Sahoo Sébastien Poncet 《Communications in Nonlinear Science & Numerical Simulation》2012,17(11):4181-4191
The steady flow arising due to the rotation of a non-Newtonian fluid at a larger distance from a stationary disk is extended to the case where the disk surface admits partial slip. The constitutive equation of the non-Newtonian fluid is modeled by that for a Reiner–Rivlin fluid. The momentum equation gives rise to a highly nonlinear boundary value problem. Numerical solution of the governing nonlinear equations are obtained over the entire range of the physical parameters. The effects of slip and non-Newtonian fluid characteristics on the momentum boundary layer are discussed in details. It is observed that slip has prominent effect on the velocity field, whereas a predominant influence of the non-Newtonian parameter is observed on the moment coefficient. 相似文献
12.
An incompressible third grade fluid occupies the porous space between two rigid infinite plates. The steady rotating flow of this fluid due to a suddenly moved lower plate with partial slip of the fluid on the plate is analysed. The fluid filling the porous space between the two plates is electrically conducting. The flow modeling is developed by employing a modified Darcy’s law. A numerical solution of the governing problem consisting of a non-linear ordinary differential equation and non-linear boundary conditions is obtained and discussed. Several limiting cases of the arising problem can be obtained by choosing suitable parameters. 相似文献
13.
R. Ellahi T. Hayat F. M. Mahomed A. Zeeshan 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2010,71(2):877-888
In this article, we use nonlinear slip conditions to investigate three fundamental flows. Constitutive equations of the third
grade fluid give rise to nonlinear equations. Exact analytic solutions of the nonlinear equations with nonlinear boundary
conditions are developed. Numerical values between the dimensionless third grade and slip parameters are tabulated. Graphs
are plotted and discussed. 相似文献
14.
R. Ellahi T. Hayat F. M. Mahomed A. Zeeshan 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2010,61(5):877-888
In this article, we use nonlinear slip conditions to investigate three fundamental flows. Constitutive equations of the third grade fluid give rise to nonlinear equations. Exact analytic solutions of the nonlinear equations with nonlinear boundary conditions are developed. Numerical values between the dimensionless third grade and slip parameters are tabulated. Graphs are plotted and discussed. 相似文献
15.
Mostafa A.A. Mahmoud Shimaa E. Waheed 《Journal of the Egyptian Mathematical Society》2012,20(1):20-27
In this work, the effects of slip velocity on the flow and heat transfer for an electrically conducting micropolar fluid over a permeable stretching surface with variable heat flux in the presence of heat generation (absorption) and a transverse magnetic field are investigated. The governing partial differential equations describing the problem are converted to a system of non-linear ordinary differential equations by using the similarity transformation, which is solved numerically using the Chebyshev spectral method. The effects of the slip parameter on the flow, micro-rotation and temperature profiles as well as on the local skin-friction coefficient, the wall couple stress and the local Nusselt number are presented graphically. The numerical results of the local skin-friction coefficient, the wall couple stress and the local Nusselt number are given in a tabular form and discussed. 相似文献
16.
The group theoretic method is applied for solving problem of combined magneto-hydrodynamic heat and mass transfer of non-Darcy natural convection about an impermeable horizontal cylinder in a non-Newtonian power law fluid embedded in porous medium under coupled thermal and mass diffusion, inertia resistance, magnetic field, thermal radiation effects. The application of one-parameter groups reduces the number of independent variables by one and consequently, the system of governing partial differential equations with the boundary conditions reduces to a system of ordinary differential equations with appropriate boundary conditions. The ordinary differential equations are solved numerically for the velocity using shooting method. The effects of magnetic parameter M, Ergun number Er, power law (viscosity) index n, buoyancy ratio N, radiation parameter Rd, Prandtl number Pr and Lewis number Le on the velocity, temperature fields within the boundary layer, heat and mass transfer are presented graphically and discussed. 相似文献
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《Communications in Nonlinear Science & Numerical Simulation》2011,16(4):1917-1930
In this investigation, thermal radiation effect over an electrically conducting, Newtonian fluid in a steady laminar magnetohydrodynamic convective flow over a porous rotating infinite disk with the consideration of heat and mass transfer in the presence of Soret and Dufour diffusion effects is investigated. The partial differential equations governing the problem under consideration are transformed by a similarity transformation into a system of ordinary differential equations which are solved numerically using fourth order Runge–Kutta based shooting method. The effects of the magnetic interaction parameter, slip flow parameter, Soret number, Dufour number, Schmidt number, radiation parameter, Prandtl number and suction parameter on the fluid velocity, temperature and concentration distributions in the regime are depicted graphically and are analyzed in detail. The corresponding skin-friction coefficients, the Nusselt number and the Sherwood number are also calculated and displayed in tables showing the effects of various parameters on them. 相似文献
19.
《Communications in Nonlinear Science & Numerical Simulation》2010,15(6):1494-1500
In this paper, we present similarity solutions for the nano boundary layer flows with Navier boundary condition. We consider viscous flows over a two-dimensional stretching surface and an axisymmetric stretching surface. The resulting nonlinear ordinary differential equations are solved analytically by the Homotopy Analysis Method. Numerical solutions are obtained by using a boundary value problem solver, and are shown to agree well with the analytical solutions. The effects of the slip parameter K and the suction parameter s on the fluid velocity and on the tangential stress are investigated and discussed. As expected, we find that for such fluid flows at nano scales, the shear stress at the wall decreases (in an absolute sense) with an increase in the slip parameter K. 相似文献
20.
The steady Von Kármán flow and heat transfer of a non-Newtonian fluid is extended to the case where the disk surface admits
partial slip. The constitutive equation of the non-Newtonian fluid is modeled by that for a Reiner-Rivlin fluid. The momentum
equations give rise to highly nonlinear boundary value problem. Numerical solutions for the governing nonlinear equations
are obtained over the entire range of the physical parameters. The effects of slip and non-Newtonian fluid characteristics
on the velocity and temperature fields have been discussed in detail and shown graphically. 相似文献