The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage dev...The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEPCMs).The versatile finite element method(FEM)is implemented to numerically solve the governing equations.The effects of various parameters,including the viscosity parameter,ranging from 1 to 3,the thermal conductivity parameter,ranging from 1 to 3,the Rayleigh parameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temperature,ranging from 1.0 to 1.2,the volume fraction of NEPCMs,ranging from 2%to 6%,the Stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility parameter,ranging from 0.1 to 0.5,are examined in detail on the temperature contours,isentropic lines,heat capacity ratio,and velocity fields.Furthermore,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented graphically.The results indicate that the time taken by the NEPCMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temperatureθf increases.Additionally,the contours of the heat capacity ratio Cr decrease with the increase in the Stefan number Ste.展开更多
Entropy analysis can help to identify the sources of entropy generation in a heat transfer process more accurately than other methods,such as energy efficiency analysis.This is because entropy analysis takes into acco...Entropy analysis can help to identify the sources of entropy generation in a heat transfer process more accurately than other methods,such as energy efficiency analysis.This is because entropy analysis takes into account the quality of energy as well as its quantity.Na-nofluids have already been shown to have superior heat transfer characteristics compared to conventionalfluids.Stefan blowing can further enhance the heat transfer capabilities of nano-fluids by increasing the massflux and turbulence at the surface.This can be beneficial in a wide range of applications,such as heat exchangers,electronic cooling,and solar energy devices.The convective boundary condition accounts for heat transfer effects,influencing temperature distribution and the thermal boundary layer.Depending on the direction of heat transfer,the convective boundary condition can induce cooling or heating effects on the inclined plate.This has practical implications for various engineering applications,such as the cooling of electronic devices or heating in industrial processes.Carreau nanofluids have a wide range of potential applications in heat transfer,energy storage,drug delivery,and food processing.This research investigates how the presence of Stefan blowing affects the properties of Carreau nanofluid flow across a convectively heated tilted plate.Heat and mass transport phenomena are studied using quadratic thermal radiation and chemical reaction parameters.The mathematical model for this work is based on the Buongiorno model.The governing equations are converted into a system of ordinary differential equations and then solved using the bvp4c solver.Physical parameters such as the mass transfer rate can be visualized using bar graphs.The study’s primary findings are that when the Weissenberg number increases,the velocity rises and the concentration profile declines due to Brownian motion.It is discovered that,when 0.5≤γ≤3(the inverse porosity parameter),the friction factor declines by 0.34001(in the presence of Stefan blowing),an展开更多
We study the effects of thermal radiation of a viscous incompressible fluid occupying a semi-infinite region of space bounded by an infinite horizontal moving hot flat plate in the presence of indirect natural convect...We study the effects of thermal radiation of a viscous incompressible fluid occupying a semi-infinite region of space bounded by an infinite horizontal moving hot flat plate in the presence of indirect natural convection by way of an induced pressure gradient. The fluid is a gray, absorbing emitting radiation but a non scattering medium. An exact solution is obtained by employing Laplace transform technique. Since temperature field depends on Reynold number the flow is considered to be non-isothermal case (the temperature of the plate Tw ≠ constant) and for an isothermal case (Tw = constant) the flow is determined by the Reynold number which is equal to 1.展开更多
文摘The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEPCMs).The versatile finite element method(FEM)is implemented to numerically solve the governing equations.The effects of various parameters,including the viscosity parameter,ranging from 1 to 3,the thermal conductivity parameter,ranging from 1 to 3,the Rayleigh parameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temperature,ranging from 1.0 to 1.2,the volume fraction of NEPCMs,ranging from 2%to 6%,the Stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility parameter,ranging from 0.1 to 0.5,are examined in detail on the temperature contours,isentropic lines,heat capacity ratio,and velocity fields.Furthermore,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented graphically.The results indicate that the time taken by the NEPCMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temperatureθf increases.Additionally,the contours of the heat capacity ratio Cr decrease with the increase in the Stefan number Ste.
基金funding this research through Researchers Supporting Project number:RSPD2024R650,King Saud University,Riyadh,Saudi Arabia.
文摘Entropy analysis can help to identify the sources of entropy generation in a heat transfer process more accurately than other methods,such as energy efficiency analysis.This is because entropy analysis takes into account the quality of energy as well as its quantity.Na-nofluids have already been shown to have superior heat transfer characteristics compared to conventionalfluids.Stefan blowing can further enhance the heat transfer capabilities of nano-fluids by increasing the massflux and turbulence at the surface.This can be beneficial in a wide range of applications,such as heat exchangers,electronic cooling,and solar energy devices.The convective boundary condition accounts for heat transfer effects,influencing temperature distribution and the thermal boundary layer.Depending on the direction of heat transfer,the convective boundary condition can induce cooling or heating effects on the inclined plate.This has practical implications for various engineering applications,such as the cooling of electronic devices or heating in industrial processes.Carreau nanofluids have a wide range of potential applications in heat transfer,energy storage,drug delivery,and food processing.This research investigates how the presence of Stefan blowing affects the properties of Carreau nanofluid flow across a convectively heated tilted plate.Heat and mass transport phenomena are studied using quadratic thermal radiation and chemical reaction parameters.The mathematical model for this work is based on the Buongiorno model.The governing equations are converted into a system of ordinary differential equations and then solved using the bvp4c solver.Physical parameters such as the mass transfer rate can be visualized using bar graphs.The study’s primary findings are that when the Weissenberg number increases,the velocity rises and the concentration profile declines due to Brownian motion.It is discovered that,when 0.5≤γ≤3(the inverse porosity parameter),the friction factor declines by 0.34001(in the presence of Stefan blowing),an
文摘We study the effects of thermal radiation of a viscous incompressible fluid occupying a semi-infinite region of space bounded by an infinite horizontal moving hot flat plate in the presence of indirect natural convection by way of an induced pressure gradient. The fluid is a gray, absorbing emitting radiation but a non scattering medium. An exact solution is obtained by employing Laplace transform technique. Since temperature field depends on Reynold number the flow is considered to be non-isothermal case (the temperature of the plate Tw ≠ constant) and for an isothermal case (Tw = constant) the flow is determined by the Reynold number which is equal to 1.
