on the onset of triple-diffusive convection in a horizontal layer of nanofluid heated from below and salted from above and below is studied both analytically and numerically. the effects of thermophoresis and brownian diffusion parameters are also introduced through buongiorno model in the governing equations. by using linear stability analysis based on perturbation theory and applying normal m...

During the last few years, a number of numerical boundary condition schemes have been used to study various aspects of the no-slip wall condition using the lattice Boltzmann method. In this paper, a modified boundary condition method is employed to simulate the no-slip wall condition in the presence of the body force term near the wall. These conditions are based on the idea of the bounce-back ...

A criterion for predicting the formation of freckles for Pb-Sn and Ni-base superalloys is evaluated using available experimental data. The criterion is based on a maximum value of the Rayleigh number, which indicates that the magnitude of buoyancy forces is largest with respect to the retarding frictional forces. The definition of the Rayleigh number involves a characteristic length scale. The ...

The main objective of this research is to analyze optimization and the thermal performance of circular porous fins with four different profiles, rectangular, convex, triangular and concave under fully wet conditions. In this research, a linear model was used for the relationship between humidity and temperature. Also, modeling is assumed one-dimensional and the temperature changes only in the d...

Steady state natural convection is numerically investigated in an enclosure using variable thermal conductivity, viscosity and thermal expansion coefficient of Al2O3–water nanofluid. This study has been conducted for a wide range of Rayleigh numbers (103≤ Ra ≤ 106), concentrations of nanoparticles (0% ≤ Φ ≤ 7%), enclosure aspect ratios (0.5 ≤ AR ≤ 2) and temperature differences between the cold...

Andrew P. Ingersoll Journal of Fluid Mechanics / Volume 25 / Issue 02 / June 1966, pp 209 ­ 228 DOI: 10.1017/S0022112066001617, Published online: 28 March 2006 Link to this article: http://journals.cambridge.org/abstract_S0022112066001617 How to cite this article: Andrew P. Ingersoll (1966). Thermal convection with shear at high Rayleigh number. Journal of Fluid Mechanics, 25, pp 209­228 doi:10...

this paper modeled heating air of a room through examining free convection in a 3d chamber. the chamber had cold and hot sources with tc and th temperatures, respectively. its other walls were adiabatic. this study aimed at predicting effect of temperature difference, displacement of hot and cold sources and their aspect ratio on flow field, temperature and heat transfer rate. to conduct the st...

The progress in our understanding of several aspects of turbulent Rayleigh-Bénard convection is reviewed. The focus is on the question of how the Nusselt number and the Reynolds number depend on the Rayleigh number Ra and the Prandtl number Pr, and on how the thicknesses of the thermal and the kinetic boundary layers scale with Ra and Pr. Non-Oberbeck-Boussinesq effects and the dynamics of the ...

The progress in our understanding of several aspects of turbulent Rayleigh-Bénard convection is reviewed. The focus is on the question of how the Nusselt number and the Reynolds number depend on the Rayleigh number Ra and the Prandtl number Pr, and on how the thicknesses of the thermal and the kinetic boundary layers scale with Ra and Pr. Non-Oberbeck-Boussinesq effects and the dynamics of the ...

In this study, a numerical examination of the significance of rotation and changeable gravitational field on the start of nanofluid convective movement in an anisotropic porous medium layer is shown. A model that accounts for the impact of Brownian diffusion and thermophoresis is used for nanofluid, while Darcy’s law is taken for the porous medium. The porous layer is subjected to uniform rotat...