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...

In this paper, simulation of natural convection heat transfer from a confined isothermal horizontal elliptic tube based on artificial neural network is presented. The experimental work with changing of all variables is time consuming and expensive and usually has problems associated with it. Experimental data used for the neural network was obtained by a Mach-Zehnder interferometer. In this stu...

A penalty finite element analysis with bi-quadratic elements is carried out to investigate the effects of uniform and non-uniform heating of inclined walls on natural convection flows within a isosceles triangular enclosure. Two cases of thermal boundary conditions are considered; case I: two inclined walls are uniformly heated while the bottom wall is cold isothermal and case II: two inclined ...

Mixed convection fluid flow and heat transfer of water-Al2O3 nanofluid inside a lid-driven square cavity has been examined numerically in order to find the optimal distribution of discrete heat sources on the wall of a cavity. The effects of different heat source length, Richardson number and Grashof number on optimal heat source location has been investigated. Moreover, the average Nusselt num...

We would like to pursue a mathematical approach to turbulence that is able to predict bulk average quantities of experimental and practical significance. Among such bulk average quantities, the Nusselt number N , the enhanced bulk average heat transfer due to convection, is perhaps the simplest physical objective of rigorous mathematical study of turbulence. The question we wish to address here...

The steady-state fully-developed laminar flow of non-Newtonian power-law fluids is examined in a circular microchannel with slip boundary condition and under an imposed constant wall heat flux. Effects of slip as well as the hydrodynamic and thermal key parameters on heat transfer and entropy generation are investigated. The results reveal that increasing the Brinkman number and the flow behavi...

flow field and heat transfer of a nanofluid, whose non-newtonian behavior has been demonstrated in the laboratory, in a square enclosure have been numerically modeled and investigated. to estimate the viscosity of nanofluid, experimental data of hong and kim, 2012 have been used, and a new model has been proposed. finally, the obtained results have been compared to those of newtonian behavior. ...

research in convective heat transfer using suspensions of nanometer-sized solid particles in base liquids started only over the past decade. recent investigations on nanofluid, as such suspensions are often called, indicate that the suspended nanoparticles remarkably change the transport properties and heat transfer characteristics of the suspension. bending walls can also improve heat transfer...