In the present study, a mathematical model of unsteady blood flow through parallel plate channel under the action of an applied constant transverse magnetic field is proposed. The model is subjected to heat source. An...In the present study, a mathematical model of unsteady blood flow through parallel plate channel under the action of an applied constant transverse magnetic field is proposed. The model is subjected to heat source. Analytical expressions are obtained by choosing the axial velocity;temperature distribution and the normal velocity of the blood depend on y and t only to convert the system of partial differential equations into system of ordinary differential equations under the conditions defined in our model. The model has been analyzed to find the effects of various parameters such as, Hartmann number, heat source parameter and Prandtl number on the axial velocity, temperature distribution and the normal velocity. The numerical solutions of axial velocity, temperature distributions and normal velocity are shown graphically for better understanding of the problem. Hence, the present mathematical model gives a simple form of axial velocity, temperature distribution and normal velocity of the blood flow so that it will help not only people working in the field of Physiological fluid dynamics but also to the medical practitioners.展开更多
Metal foam material,which serves as an alternative replacement of the conventional flow distributor of proton exchange membrane(PEM)fuel cell,has been attracting much attention over last few decades.In this work,three...Metal foam material,which serves as an alternative replacement of the conventional flow distributor of proton exchange membrane(PEM)fuel cell,has been attracting much attention over last few decades.In this work,three-dimensional modeling work for PEM fuel cell containing metal foam as cathode flow distributor has been carried out.The fuel cell performance and operating characteristics of metal foam flow field and conventional parallel flow channel have been compared and discussed.The cell performance has been reasonably validated based on the corresponding experimental tests conducted in this study.The superior performance of PEM fuel cell with metal foam as cathode flow field benefits a lot from the uniform gas flow.The porous metal foam material provides more pathways for the water delivery at the interface of metal foam flow field and gas diffusion layer(GDL),accelerating water removal capability of cathode.Because of the significant oxygen transfer loss in diffusion limited parallel channel,the operation of PEM fuel cell with parallel channel is found to be more sensitive to cathode humidification and oxygen supply at inlet.Due to the more uniform and effective electron transport though the porous electrode,it is possible to use thinner GDL in metal foam PEM fuel cell.It is expected that this study could give a good baseline of operating behavior of PEM fuel cell with metal foam flow distributor.展开更多
文摘In the present study, a mathematical model of unsteady blood flow through parallel plate channel under the action of an applied constant transverse magnetic field is proposed. The model is subjected to heat source. Analytical expressions are obtained by choosing the axial velocity;temperature distribution and the normal velocity of the blood depend on y and t only to convert the system of partial differential equations into system of ordinary differential equations under the conditions defined in our model. The model has been analyzed to find the effects of various parameters such as, Hartmann number, heat source parameter and Prandtl number on the axial velocity, temperature distribution and the normal velocity. The numerical solutions of axial velocity, temperature distributions and normal velocity are shown graphically for better understanding of the problem. Hence, the present mathematical model gives a simple form of axial velocity, temperature distribution and normal velocity of the blood flow so that it will help not only people working in the field of Physiological fluid dynamics but also to the medical practitioners.
基金supported by the National Natural Science Foundation of China (Grant No.51921004)the Natural Science Foundation for Outstanding Young Scholars of Tianjin (Grant No.18JCJQJC46700)。
文摘Metal foam material,which serves as an alternative replacement of the conventional flow distributor of proton exchange membrane(PEM)fuel cell,has been attracting much attention over last few decades.In this work,three-dimensional modeling work for PEM fuel cell containing metal foam as cathode flow distributor has been carried out.The fuel cell performance and operating characteristics of metal foam flow field and conventional parallel flow channel have been compared and discussed.The cell performance has been reasonably validated based on the corresponding experimental tests conducted in this study.The superior performance of PEM fuel cell with metal foam as cathode flow field benefits a lot from the uniform gas flow.The porous metal foam material provides more pathways for the water delivery at the interface of metal foam flow field and gas diffusion layer(GDL),accelerating water removal capability of cathode.Because of the significant oxygen transfer loss in diffusion limited parallel channel,the operation of PEM fuel cell with parallel channel is found to be more sensitive to cathode humidification and oxygen supply at inlet.Due to the more uniform and effective electron transport though the porous electrode,it is possible to use thinner GDL in metal foam PEM fuel cell.It is expected that this study could give a good baseline of operating behavior of PEM fuel cell with metal foam flow distributor.