In this study,magneto-hydrodynamics (MHD) mixed convection effects of Al2O3-water nanofluid flow over a backward-facing step were investigated numerically for various electrical conductivity models of nanofluids.A uni...In this study,magneto-hydrodynamics (MHD) mixed convection effects of Al2O3-water nanofluid flow over a backward-facing step were investigated numerically for various electrical conductivity models of nanofluids.A uniform external magnetic field was applied to the flow and strength of magnetic field was varied with different values of dimensionless parameter Hartmann number (Ha=0,10,20,30,40).Three different electrical conductivity models were used to see the effects of MHD nanofluid flow.Besides,five different inclination angles between 0°-90° is used for the external magnetic field.The problem geometry is a backward-facing step which is used in many engineering applications where flow separation and reattachment phenomenon occurs.Mixed type convective heat transfer of backward-facing step was examined with various values of Richardson number (Ri=0.01,0.1,1,10) and four different nanoparticle volume fractions (Ф=0.01,0.015,0.020,0.025) considering different electrical conductivity models.Finite element method via commercial code COMSOL was used for computations.Results indicate that the addition of nanoparticles enhanced heat transfer significantly.Also increasing magnetic field strength and inclination angle increased heat transfer rate.Effects of different electrical conductivity models were also investigated and it was observed that they have significant effects on the fluid flow and heat transfer characteristics in the presence of magnetic field.展开更多
Web 2.0-based online communities and social networking platforms in particular enable users to create their own content, share this content with anyone they invite and organize connections with existing or new online ...Web 2.0-based online communities and social networking platforms in particular enable users to create their own content, share this content with anyone they invite and organize connections with existing or new online contacts. The underlying processes are self-directed and represent a valuable source for creativity and innovation---especially outside firms＇ boundaries. The basis for the authors＇ research in progress is a framework which focuses on the relations between intrinsic motivation, creativity and Web 2.0-based online communities or social networking platforms. First results of the authors＇ exploratory empirical investigation of a specific social networking platform suggest that the authors＇ two propositions are valid.展开更多
文摘In this study,magneto-hydrodynamics (MHD) mixed convection effects of Al2O3-water nanofluid flow over a backward-facing step were investigated numerically for various electrical conductivity models of nanofluids.A uniform external magnetic field was applied to the flow and strength of magnetic field was varied with different values of dimensionless parameter Hartmann number (Ha=0,10,20,30,40).Three different electrical conductivity models were used to see the effects of MHD nanofluid flow.Besides,five different inclination angles between 0°-90° is used for the external magnetic field.The problem geometry is a backward-facing step which is used in many engineering applications where flow separation and reattachment phenomenon occurs.Mixed type convective heat transfer of backward-facing step was examined with various values of Richardson number (Ri=0.01,0.1,1,10) and four different nanoparticle volume fractions (Ф=0.01,0.015,0.020,0.025) considering different electrical conductivity models.Finite element method via commercial code COMSOL was used for computations.Results indicate that the addition of nanoparticles enhanced heat transfer significantly.Also increasing magnetic field strength and inclination angle increased heat transfer rate.Effects of different electrical conductivity models were also investigated and it was observed that they have significant effects on the fluid flow and heat transfer characteristics in the presence of magnetic field.
文摘Web 2.0-based online communities and social networking platforms in particular enable users to create their own content, share this content with anyone they invite and organize connections with existing or new online contacts. The underlying processes are self-directed and represent a valuable source for creativity and innovation---especially outside firms＇ boundaries. The basis for the authors＇ research in progress is a framework which focuses on the relations between intrinsic motivation, creativity and Web 2.0-based online communities or social networking platforms. First results of the authors＇ exploratory empirical investigation of a specific social networking platform suggest that the authors＇ two propositions are valid.
