The exact solutions for the viscous fluid through a porous slit with linear ab- sorption are obtained. The Stokes equation with non-homogeneous boundary conditions is solved to get the expressions for the velocity com...The exact solutions for the viscous fluid through a porous slit with linear ab- sorption are obtained. The Stokes equation with non-homogeneous boundary conditions is solved to get the expressions for the velocity components, pressure distribution, wall shear stress, fractional absorption, and leakage flux. The volume flow rate and mean flow rate are found to be useful in obtaining a convenient form of the longitudinal velocity component and pressure difference. The points of the maximum velocity components for a fixed axial distance are identified. The value of the linear absorption parameter is ran- domly chosen, and the rest available data of the rat kidney to the tabulate pressure drop and fractional absorption are incorporated. The effects of the linear absorption, uniform absorption, and flow rate parameters on the flow properties are discussed by graphs. It is found that forward flow occurs only if the volume flux per unit width is greater than the absorption velocity throughout the length of the slit, otherwise back flow may occur. The leakage flux increases with the increase in the linear absorption parameter. Streamlines are drawn to help the analysis of the flow behaviors during the absorption of the fluid flow through the renal tubule and purification of blood through an artificial kidney.展开更多
The present paper is concerned with the steady thin film flow of the Sisko fluid on a horizontal moving plate, where the surface tension gradient is a driving mechanism. The analytic solution for the resulting nonline...The present paper is concerned with the steady thin film flow of the Sisko fluid on a horizontal moving plate, where the surface tension gradient is a driving mechanism. The analytic solution for the resulting nonlinear ordinary differential equation is obtained by the Adomian decomposition method （ADM）. The physical quantities are derived including the pressure profile, the velocity profile, the maximum residue time, the stationary points, the volume flow rate, the average film velocity, the uniform film thickness, the shear stress, the surface tension profile~ and the vorticity vector. It is found that the velocity of the Sisko fluid film decreases when the fluid behavior index and the Sisko fluid parameter increase, whereas it increases with an increase in the inverse capillary number. An increase in the inverse capillary number results in an increase in the surface tension which in turn results in an increase in the surface tension gradient on the Sisko fluid film. The locations of the stationary points are shifted towards the moving plate with the increase in the inverse capillary number, and vice versa locations for the stationary points are found with the increasing Sisko fluid parameter. Furthermore, shear thinning and shear thickening characteristics of the Sisko fluid are discussed. A comparison is made between the Sisko fluid film and the Newtonian fluid film.展开更多
The present theoretical assessment deals with the peristaltic-ciliary trans- port of a developing embryo within a fallopian tubal fluid in the human fallopian tube. A mathematical model of peristalsis-cilia induced fl...The present theoretical assessment deals with the peristaltic-ciliary trans- port of a developing embryo within a fallopian tubal fluid in the human fallopian tube. A mathematical model of peristalsis-cilia induced flow of a linearly viscous fluid within a fallopian tubal fluid in a finite two-dimensional narrow tube is developed. The lubrica- tion approximation theory is used to solve the resulting partial differential equation. The expressions for axial and radial velocities, pressure gradient, stream function, volume flow rate, and time mean volume flow rate are derived. Numerical integration is performed for the appropriate residue time over the wavelength and the pressure difference over the wavelength. Moreover, the plots of axial velocity, the appropriate residue time over wavelength, the vector, the pressure difference over wavelength, and the streamlines are displayed and discussed for emerging parameters and constants. Salient features of the pumping characteristics and the trapping phenomenon are discussed in detail. Yhrther- more, a comparison between the peristaltic flow and the peristaltic-ciliary flow is made as the special case. Relevance of the current results to the transport of a developing embryo within a fallopian tubal fluid from ampulla to the intramural in the fallopian tube is also explored. It reveals the fact that cilia along with peristalsis helps to complete the required mitotic divisions while transporting the developing embryo within a fallopian tubal fluid in the human fallopian tube.展开更多
We present an attempt to study the influence of couple stresses on the flow induced by an infinite disk rotating with a constant angular velocity.The governing equations of motion in three dimensions are treated analy...We present an attempt to study the influence of couple stresses on the flow induced by an infinite disk rotating with a constant angular velocity.The governing equations of motion in three dimensions are treated analytically yielding the derivation of exact solutions which differ from those corresponding to the classical Von Kármán's flow.The analysis reveals that a boundary layer structure develops near the surface of the disk,whose far-field behaviour is distinct from the near-wall solution.The velocity and vorticity components for various values of the dimensionless parameters,associated with the flow,are presented graphically.展开更多
In this study,carbon black(CB)powder-loaded polyurethane(PU)composites(CB-PU composites)were prepared by melt mixing method with different volume percentages(45,50,55,58 and 61 vol.%)of CB in the PU matrix.The prepare...In this study,carbon black(CB)powder-loaded polyurethane(PU)composites(CB-PU composites)were prepared by melt mixing method with different volume percentages(45,50,55,58 and 61 vol.%)of CB in the PU matrix.The prepared CB-PU composites had been further studied for surface morphology using the field-emission scanning electron microscopy(FESEM)technique.Dielectric properties in terms of real permittivity(ε′)and imaginary permittivity(ε′′)of the fabricated composites were computed using an Agilent E8364B vector network analyzer in the frequency range of 8-12 GHz(X-band).Dielectric loss factor of the prepared CB-PU composites was computed in terms of the dielectric loss tangent(tanδ_(e)=ε′′/ε′).Microwave absorbing properties were appraised in terms of the reflection loss(RL)which in turn was calculated for varying thicknesses of the prepared composites from the measured real and imaginary permittivity data.The minimum RL was observed as−20.10 dB for the absorber with a thickness of 2.2 mm and the bandwidth achieved was 1.92 GHz for RL≤−10 dB.Based on the above results these CB-PU composites have potential use as effective microwave absorbers in 8-12-GHz(X-band)frequency range.展开更多
文摘The exact solutions for the viscous fluid through a porous slit with linear ab- sorption are obtained. The Stokes equation with non-homogeneous boundary conditions is solved to get the expressions for the velocity components, pressure distribution, wall shear stress, fractional absorption, and leakage flux. The volume flow rate and mean flow rate are found to be useful in obtaining a convenient form of the longitudinal velocity component and pressure difference. The points of the maximum velocity components for a fixed axial distance are identified. The value of the linear absorption parameter is ran- domly chosen, and the rest available data of the rat kidney to the tabulate pressure drop and fractional absorption are incorporated. The effects of the linear absorption, uniform absorption, and flow rate parameters on the flow properties are discussed by graphs. It is found that forward flow occurs only if the volume flux per unit width is greater than the absorption velocity throughout the length of the slit, otherwise back flow may occur. The leakage flux increases with the increase in the linear absorption parameter. Streamlines are drawn to help the analysis of the flow behaviors during the absorption of the fluid flow through the renal tubule and purification of blood through an artificial kidney.
文摘The present paper is concerned with the steady thin film flow of the Sisko fluid on a horizontal moving plate, where the surface tension gradient is a driving mechanism. The analytic solution for the resulting nonlinear ordinary differential equation is obtained by the Adomian decomposition method （ADM）. The physical quantities are derived including the pressure profile, the velocity profile, the maximum residue time, the stationary points, the volume flow rate, the average film velocity, the uniform film thickness, the shear stress, the surface tension profile~ and the vorticity vector. It is found that the velocity of the Sisko fluid film decreases when the fluid behavior index and the Sisko fluid parameter increase, whereas it increases with an increase in the inverse capillary number. An increase in the inverse capillary number results in an increase in the surface tension which in turn results in an increase in the surface tension gradient on the Sisko fluid film. The locations of the stationary points are shifted towards the moving plate with the increase in the inverse capillary number, and vice versa locations for the stationary points are found with the increasing Sisko fluid parameter. Furthermore, shear thinning and shear thickening characteristics of the Sisko fluid are discussed. A comparison is made between the Sisko fluid film and the Newtonian fluid film.
文摘The present theoretical assessment deals with the peristaltic-ciliary trans- port of a developing embryo within a fallopian tubal fluid in the human fallopian tube. A mathematical model of peristalsis-cilia induced flow of a linearly viscous fluid within a fallopian tubal fluid in a finite two-dimensional narrow tube is developed. The lubrica- tion approximation theory is used to solve the resulting partial differential equation. The expressions for axial and radial velocities, pressure gradient, stream function, volume flow rate, and time mean volume flow rate are derived. Numerical integration is performed for the appropriate residue time over the wavelength and the pressure difference over the wavelength. Moreover, the plots of axial velocity, the appropriate residue time over wavelength, the vector, the pressure difference over wavelength, and the streamlines are displayed and discussed for emerging parameters and constants. Salient features of the pumping characteristics and the trapping phenomenon are discussed in detail. Yhrther- more, a comparison between the peristaltic flow and the peristaltic-ciliary flow is made as the special case. Relevance of the current results to the transport of a developing embryo within a fallopian tubal fluid from ampulla to the intramural in the fallopian tube is also explored. It reveals the fact that cilia along with peristalsis helps to complete the required mitotic divisions while transporting the developing embryo within a fallopian tubal fluid in the human fallopian tube.
文摘We present an attempt to study the influence of couple stresses on the flow induced by an infinite disk rotating with a constant angular velocity.The governing equations of motion in three dimensions are treated analytically yielding the derivation of exact solutions which differ from those corresponding to the classical Von Kármán's flow.The analysis reveals that a boundary layer structure develops near the surface of the disk,whose far-field behaviour is distinct from the near-wall solution.The velocity and vorticity components for various values of the dimensionless parameters,associated with the flow,are presented graphically.
文摘In this study,carbon black(CB)powder-loaded polyurethane(PU)composites(CB-PU composites)were prepared by melt mixing method with different volume percentages(45,50,55,58 and 61 vol.%)of CB in the PU matrix.The prepared CB-PU composites had been further studied for surface morphology using the field-emission scanning electron microscopy(FESEM)technique.Dielectric properties in terms of real permittivity(ε′)and imaginary permittivity(ε′′)of the fabricated composites were computed using an Agilent E8364B vector network analyzer in the frequency range of 8-12 GHz(X-band).Dielectric loss factor of the prepared CB-PU composites was computed in terms of the dielectric loss tangent(tanδ_(e)=ε′′/ε′).Microwave absorbing properties were appraised in terms of the reflection loss(RL)which in turn was calculated for varying thicknesses of the prepared composites from the measured real and imaginary permittivity data.The minimum RL was observed as−20.10 dB for the absorber with a thickness of 2.2 mm and the bandwidth achieved was 1.92 GHz for RL≤−10 dB.Based on the above results these CB-PU composites have potential use as effective microwave absorbers in 8-12-GHz(X-band)frequency range.
