The paper deals with the theoretical investigation of a fundamental problem of biomaguetic fluid flow through a porous medium subject to a magnetic field by using the principles of biomagnetic fluid dynamics （BFD）. ...The paper deals with the theoretical investigation of a fundamental problem of biomaguetic fluid flow through a porous medium subject to a magnetic field by using the principles of biomagnetic fluid dynamics （BFD）. The study pertains to a situation where magnetization of the fluid varies with temperature. The fluid is considered to be non-Newtonian, whose flow is governed by the equation of a second-grade viscoelastic fluid. The walls of the channel are assumed to be stretchable, where the surface velocity is proportional to the longitudinal distance from the origin of coordinates. The problem is first reduced to solving a system of coupled nonlinear differential equations involving seven parameters. Considering blood as a biomagnetic fluid and using the present analysis, an attempt is made to compute some parameters of the blood flow by developing a suitable numerical method and by devising an appropriate finite difference scheme. The computational results are presented in graphical form, and thereby some theoretical predictions are made with respect to the hemodynamical flow of the blood in a hyperthermal state under the action of a magnetic field. The results clearly indicate that the presence of a magnetic dipole bears the potential so as to affect the characteristics of the blood flow in arteries to a significant extent during the therapeutic procedure of electromagnetic hyperthermia. The study will attract the attention of clinicians, to whom the results would be useful in the treatment of cancer patients by the method of electromagnetic hyperthermia.展开更多
The magnetohydrodynamic (MHD) graphene-polydimethylsiloxane (PDMS) nanofluid flow between two squeezing parallel plates in the presence of thermal radiation effects is investigated. The energy efficiency of the system...The magnetohydrodynamic (MHD) graphene-polydimethylsiloxane (PDMS) nanofluid flow between two squeezing parallel plates in the presence of thermal radiation effects is investigated. The energy efficiency of the system via the Bejan number is studied extensively. The governing partial differential equations are converted by using the similarity transformations into a set of coupled ordinary differential equations. The set of these converted equations is solved by using the differential transform method (DTM). The entropy generation in terms of the Bejan number, the coefficient of skin-friction, and the heat transfer rate is furthermore investigated under the effects of various physical parameters of interest. The present study shows that the Bejan number, the velocity and thermal profiles, and the rate of heat transfer decrease with a rise in the Deborah number De while the skin-friction coefficient increases. It is also observed that the entropy generation due to frictional forces is higher than that due to thermal effects. Thus, the study bears the potential application in powder technology as well as in biomedical engineering.展开更多
The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss...The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss＇s law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices.展开更多
This paper investigates the effects of thermal radiation on the magnetohy- drodynamic （MHD） flow and heat transfer over a nonlinear shrinking porous sheet. The surface velocity of the shrinking sheet and the transve...This paper investigates the effects of thermal radiation on the magnetohy- drodynamic （MHD） flow and heat transfer over a nonlinear shrinking porous sheet. The surface velocity of the shrinking sheet and the transverse magnetic field are assumed to vary as a power function of the distance from the origin. The temperature dependent viscosity and the thermal conductivity are also assumed to vary as an inverse function and a linear function of the temperature, respectively. A generalized similarity transfor- mation is used to reduce the governing partial differential equations to their nonlinear coupled ordinary differential equations, and is solved numerically by using a finite difference scheme. The numerical results concern with the velocity and temperature profiles as well as the local skin-friction coefficient and the rate of the heat transfer at the porous sheet for different values of several physical parameters of interest.展开更多
文摘The paper deals with the theoretical investigation of a fundamental problem of biomaguetic fluid flow through a porous medium subject to a magnetic field by using the principles of biomagnetic fluid dynamics （BFD）. The study pertains to a situation where magnetization of the fluid varies with temperature. The fluid is considered to be non-Newtonian, whose flow is governed by the equation of a second-grade viscoelastic fluid. The walls of the channel are assumed to be stretchable, where the surface velocity is proportional to the longitudinal distance from the origin of coordinates. The problem is first reduced to solving a system of coupled nonlinear differential equations involving seven parameters. Considering blood as a biomagnetic fluid and using the present analysis, an attempt is made to compute some parameters of the blood flow by developing a suitable numerical method and by devising an appropriate finite difference scheme. The computational results are presented in graphical form, and thereby some theoretical predictions are made with respect to the hemodynamical flow of the blood in a hyperthermal state under the action of a magnetic field. The results clearly indicate that the presence of a magnetic dipole bears the potential so as to affect the characteristics of the blood flow in arteries to a significant extent during the therapeutic procedure of electromagnetic hyperthermia. The study will attract the attention of clinicians, to whom the results would be useful in the treatment of cancer patients by the method of electromagnetic hyperthermia.
基金financial support through the Junior Research Fellowship (JRF) (No. 21/06/2015(i)EU-V)
文摘The magnetohydrodynamic (MHD) graphene-polydimethylsiloxane (PDMS) nanofluid flow between two squeezing parallel plates in the presence of thermal radiation effects is investigated. The energy efficiency of the system via the Bejan number is studied extensively. The governing partial differential equations are converted by using the similarity transformations into a set of coupled ordinary differential equations. The set of these converted equations is solved by using the differential transform method (DTM). The entropy generation in terms of the Bejan number, the coefficient of skin-friction, and the heat transfer rate is furthermore investigated under the effects of various physical parameters of interest. The present study shows that the Bejan number, the velocity and thermal profiles, and the rate of heat transfer decrease with a rise in the Deborah number De while the skin-friction coefficient increases. It is also observed that the entropy generation due to frictional forces is higher than that due to thermal effects. Thus, the study bears the potential application in powder technology as well as in biomedical engineering.
文摘The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss＇s law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices.
基金Project supported by the Department of Science and Technology, Government of India (DST-GOI)Funded Promotion of University Research and Scientific Excellence (PURSE) Programme of Jadavpur University (No. SR/S9/Z-23/2008/5)
文摘This paper investigates the effects of thermal radiation on the magnetohy- drodynamic （MHD） flow and heat transfer over a nonlinear shrinking porous sheet. The surface velocity of the shrinking sheet and the transverse magnetic field are assumed to vary as a power function of the distance from the origin. The temperature dependent viscosity and the thermal conductivity are also assumed to vary as an inverse function and a linear function of the temperature, respectively. A generalized similarity transfor- mation is used to reduce the governing partial differential equations to their nonlinear coupled ordinary differential equations, and is solved numerically by using a finite difference scheme. The numerical results concern with the velocity and temperature profiles as well as the local skin-friction coefficient and the rate of the heat transfer at the porous sheet for different values of several physical parameters of interest.
