The rheological features of an incompressible axi-symmetric Casson-Maxwell nanofluid flow between two stationary disks are examined.The lower permeable disk is located at z=-a,while the upper disk is placed at z=a.Bot...The rheological features of an incompressible axi-symmetric Casson-Maxwell nanofluid flow between two stationary disks are examined.The lower permeable disk is located at z=-a,while the upper disk is placed at z=a.Both the disks are porous and subjected to uniform injection.The fluid properties such as thermal conductivity vary with temperature.The Cattaneo-Christov thermal expression is implemented along with the Buongiorno nanofluid theory.By operating the similarity functions,the reduced form of the fluid model in terms of ordinary differential equations is obtained and solved by the bvp4 c numerical technique.The physical quantities are demonstrated graphically on the velocity and temperature fields.Three-dimensional flow arrangements and twodimensional contour patterns against several dimensionless variables are also sketched.The numerical values of the local Nusselt and Sherwood numbers for various quantities are presented in tabular set-up.The intensity of the linear relationship between the Nusselt and Sherwood numbers is assessed through Pearson’s product-moment correlation technique.The statistical implication of the linear association between variables is also examined by the t-test statistic approach.展开更多
The conservation equations for heat conduction are established based on the concept of thermal mass.We obtain a general heat conduction law which takes into account the spatial and temporal inertia of thermal mass.The...The conservation equations for heat conduction are established based on the concept of thermal mass.We obtain a general heat conduction law which takes into account the spatial and temporal inertia of thermal mass.The general law introduces a damped thermal wave equation.It reduces to the well-known CV model when the spatial inertia of heat flux and temperature and the temporal inertia of temperature are neglected,which indicates that the CV model only considers the temporal inertia of heat flux.Numerical simulations on the propagation and superposition of thermal waves show that for small thermal perturbation the CV model agrees with the thermal wave equation based on the thermal mass theory.For larger thermal perturbation,however,the physically impossible phenomenon pre-dicted by CV model,i.e.the negative temperature induced by the thermal wave superposition,is eliminated by the general heat conduction law,which demonstrates that the present heat conduction law based on the thermal mass theory is more reasonable.展开更多
文摘The rheological features of an incompressible axi-symmetric Casson-Maxwell nanofluid flow between two stationary disks are examined.The lower permeable disk is located at z=-a,while the upper disk is placed at z=a.Both the disks are porous and subjected to uniform injection.The fluid properties such as thermal conductivity vary with temperature.The Cattaneo-Christov thermal expression is implemented along with the Buongiorno nanofluid theory.By operating the similarity functions,the reduced form of the fluid model in terms of ordinary differential equations is obtained and solved by the bvp4 c numerical technique.The physical quantities are demonstrated graphically on the velocity and temperature fields.Three-dimensional flow arrangements and twodimensional contour patterns against several dimensionless variables are also sketched.The numerical values of the local Nusselt and Sherwood numbers for various quantities are presented in tabular set-up.The intensity of the linear relationship between the Nusselt and Sherwood numbers is assessed through Pearson’s product-moment correlation technique.The statistical implication of the linear association between variables is also examined by the t-test statistic approach.
基金Supported by the National Natural Science Foundation of China(Grant No.50606018)
文摘The conservation equations for heat conduction are established based on the concept of thermal mass.We obtain a general heat conduction law which takes into account the spatial and temporal inertia of thermal mass.The general law introduces a damped thermal wave equation.It reduces to the well-known CV model when the spatial inertia of heat flux and temperature and the temporal inertia of temperature are neglected,which indicates that the CV model only considers the temporal inertia of heat flux.Numerical simulations on the propagation and superposition of thermal waves show that for small thermal perturbation the CV model agrees with the thermal wave equation based on the thermal mass theory.For larger thermal perturbation,however,the physically impossible phenomenon pre-dicted by CV model,i.e.the negative temperature induced by the thermal wave superposition,is eliminated by the general heat conduction law,which demonstrates that the present heat conduction law based on the thermal mass theory is more reasonable.
