The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow mo...The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow model.The formulation of the flow model is based on basic universal equations of conservation of momentum,energy and mass.The prescribed flow model is converted to non-dimensional form by using suitable scaling.The obtained transformed equations are solved numerically by using finite difference scheme.For the analysis of above said behavior the computed numerical data for fluid velocity,temperature profile,and mass concentration for several constraints that is mixed convection parameterλt,modified mixed convection parameterλc,Prandtl number Pr,heat generation/absorption parameterδ,Schmidt number Sc,thermophoresis parameter Nt,and thermophoretic coefficient k are sketched in graphical form.Numerical results for skin friction,heat transfer rate and the mass transfer rate are tabulated for various emerging physical parameters.It is reported that in enhancement in heat,generation boosts up the fluid temperature at some positions of the surface of the sphere.As heat absorption parameter is decreased temperature field increases at position X=π/4 on the other hand,no alteration at other considered circumferential positions is noticed.展开更多
The present work emphasizes the significance of oscillatory mixed convection stratified fluid and heat transfer characteristics at different stations of non-conducting horizontally circular cylinder in the presence of...The present work emphasizes the significance of oscillatory mixed convection stratified fluid and heat transfer characteristics at different stations of non-conducting horizontally circular cylinder in the presence of thermally stratified medium.To remove the difficulties in illustrating the coupled PDE’s,the finite-difference scheme with efficient primitive-variable formulation is proposed to transform dimensionless equations.The numerical simulations of coupled non-dimensional equations are computed in terms velocity of fluid,temperature and magnetic field which are computed to examine the fluctuating components of skin friction,heat transfer and current density for various emerging parameters.The governing parameters namely,thermally stratification parameter𝑆𝑆𝑡𝑡,mixed-convection parameter𝜆𝜆,Prandtl number Pr,magnetic force parameter𝜉𝜉and magnetic-Prandtl number𝛾𝛾are displayed graphically at selected values for velocity and heat transfer mechanism.It is computed that heat transfer attains maximum amplitude and good variations in the presence of thermally stratified parameter at each position𝛼𝛼=𝜋𝜋6⁄,𝛼𝛼=𝜋𝜋3⁄and𝛼𝛼=𝜋𝜋around the surface of non-conducting horizontally cylinder.The velocity of fluid attains certain height at station𝛼𝛼=𝜋𝜋6⁄for higher value of stratification parameter.It is also found that the temperature gradient decreases with stratification parameter𝑆𝑆𝑡𝑡,but it increases after a certain distance𝑌𝑌from the cylinder.The novelty of the current work is that due to non-conducting phenomena the magnetic effects are strongly observed far from the surface but exact at the surface are zero for each position.展开更多
A kinetic flux-vector splitting (KFVS) scheme is applied for solving a reduced six-equation two-phase flow model of Saurel et al. [1]. The model incorporates single velocity, two pressures and relaxation terms. An add...A kinetic flux-vector splitting (KFVS) scheme is applied for solving a reduced six-equation two-phase flow model of Saurel et al. [1]. The model incorporates single velocity, two pressures and relaxation terms. An additional seventh equation, describing the total mixture energy, is added to the model to guarantee the correct treatment of shocks in the single phase limit. Some salient features of the model are that it is hyperbolic with only three wave propagation speeds and the volume fraction remains positive. The proposed numerical scheme is based on the direct splitting of macroscopic flux functions of the system of equations. The second order accuracy of the scheme is achieved by using MUSCL-type initial reconstruction and Runge-Kutta time stepping method. Moreover, a pressure relaxation procedure is used to fulfill the interface conditions. For validation, the results of suggested scheme are compared with those from the high resolution central upwind and HLLC schemes. The central upwind scheme is also applied for the first time to this model. The accuracy, efficiency and simplicity of the KFVS scheme demonstrate its potential for modeling two-phase flows.展开更多
基金The authors would like to acknowledge Natural Science Foundation of China(Grant Nos.61673169,11701176,11626101,11601485).
文摘The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow model.The formulation of the flow model is based on basic universal equations of conservation of momentum,energy and mass.The prescribed flow model is converted to non-dimensional form by using suitable scaling.The obtained transformed equations are solved numerically by using finite difference scheme.For the analysis of above said behavior the computed numerical data for fluid velocity,temperature profile,and mass concentration for several constraints that is mixed convection parameterλt,modified mixed convection parameterλc,Prandtl number Pr,heat generation/absorption parameterδ,Schmidt number Sc,thermophoresis parameter Nt,and thermophoretic coefficient k are sketched in graphical form.Numerical results for skin friction,heat transfer rate and the mass transfer rate are tabulated for various emerging physical parameters.It is reported that in enhancement in heat,generation boosts up the fluid temperature at some positions of the surface of the sphere.As heat absorption parameter is decreased temperature field increases at position X=π/4 on the other hand,no alteration at other considered circumferential positions is noticed.
文摘The present work emphasizes the significance of oscillatory mixed convection stratified fluid and heat transfer characteristics at different stations of non-conducting horizontally circular cylinder in the presence of thermally stratified medium.To remove the difficulties in illustrating the coupled PDE’s,the finite-difference scheme with efficient primitive-variable formulation is proposed to transform dimensionless equations.The numerical simulations of coupled non-dimensional equations are computed in terms velocity of fluid,temperature and magnetic field which are computed to examine the fluctuating components of skin friction,heat transfer and current density for various emerging parameters.The governing parameters namely,thermally stratification parameter𝑆𝑆𝑡𝑡,mixed-convection parameter𝜆𝜆,Prandtl number Pr,magnetic force parameter𝜉𝜉and magnetic-Prandtl number𝛾𝛾are displayed graphically at selected values for velocity and heat transfer mechanism.It is computed that heat transfer attains maximum amplitude and good variations in the presence of thermally stratified parameter at each position𝛼𝛼=𝜋𝜋6⁄,𝛼𝛼=𝜋𝜋3⁄and𝛼𝛼=𝜋𝜋around the surface of non-conducting horizontally cylinder.The velocity of fluid attains certain height at station𝛼𝛼=𝜋𝜋6⁄for higher value of stratification parameter.It is also found that the temperature gradient decreases with stratification parameter𝑆𝑆𝑡𝑡,but it increases after a certain distance𝑌𝑌from the cylinder.The novelty of the current work is that due to non-conducting phenomena the magnetic effects are strongly observed far from the surface but exact at the surface are zero for each position.
文摘A kinetic flux-vector splitting (KFVS) scheme is applied for solving a reduced six-equation two-phase flow model of Saurel et al. [1]. The model incorporates single velocity, two pressures and relaxation terms. An additional seventh equation, describing the total mixture energy, is added to the model to guarantee the correct treatment of shocks in the single phase limit. Some salient features of the model are that it is hyperbolic with only three wave propagation speeds and the volume fraction remains positive. The proposed numerical scheme is based on the direct splitting of macroscopic flux functions of the system of equations. The second order accuracy of the scheme is achieved by using MUSCL-type initial reconstruction and Runge-Kutta time stepping method. Moreover, a pressure relaxation procedure is used to fulfill the interface conditions. For validation, the results of suggested scheme are compared with those from the high resolution central upwind and HLLC schemes. The central upwind scheme is also applied for the first time to this model. The accuracy, efficiency and simplicity of the KFVS scheme demonstrate its potential for modeling two-phase flows.
