The Ra and Pr number scaling of the Nusselt number Nu, the Reynolds number Re, the temperature fluctuations, and the kinetic and thermal dissipation rates is studied for snumericald homogeneous Rayleigh–Bénard turbulence, i.e., Rayleigh–Bénard turbulence with periodic boundary conditions in all directions and a volume forcing of the temperature field by a mean gradient. This system serves as mo...

We study the fine-scale statistics of temperature and its derivatives in turbulent RayleighBénard convection. Direct numerical simulations are carried out in a cylindrical cell with unit aspect ratio filled with a fluid with Prandtl number equal to 0.7 for Rayleigh numbers between 10 and 10. The probability density function of the temperature or its fluctuations is found to be always non-Gaussi...

In this paper, the bioconvective flow in a porous square cavity containing oxytactic microorganism in the presence of chemical reaction is investigated. The bioconvection flow and heat transfer in porous media are formulated based on the Darcy model of Boussinesq approximation. The governing partial differential equations are solved using the Galerkin finite element method. The computational nu...

This investigation is a three dimensional comprehensive heat transfer analysis for partially differentially heated enclosure with the vertical fin mounted on the hot wall. The thermal lattice Boltzmann based on D3Q19 method is utilized to illustrate the effects of vertical fins and nanoparticles on the flow and thermal fields. The effects of Rayleigh number and different arrangement of fins on ...

The roll of melting heat transfer on magnetohydrodynamic natural convection in a square enclosure with heating of bottom wall is examined numerically in this article. The dimensionless governing partial differential equations are transformed into vorticity and stream function formulation and then solved using the finite difference method (FDM). The effects of thermal Rayleigh number (Ra</em...

Natural convection heat transfer has many applications in different fields of industry; such as cooling industries, electronic transformer devices and ventilation equipment; due to simple process, economic advantage, low noise and renewed retrieval. Recently, heat transfer of nanofluids have been considered because of higher thermal conductivity coefficient compared with those of ordinary fluid...

in this paper, the effect of the brownian term in natural convection of cuo-water nanofluid inside a partially filled porous cavity, with internal heat generation has been studied. it is assumed that the viscosity and thermal conductivity of nanofluid consists of a static part and a brownian part of which is a function of temperature and the volume fraction of nanofluid. because of internal hea...

natural convection heat transfer has many applications in different fields of industry; such as cooling industries, electronic transformer devices and ventilation equipment; due to simple process, economic advantage, low noise and renewed retrieval. recently, heat transfer of nanofluids have been considered because of higher thermal conductivity coefficient compared with those of ordinary fluid...