In this paper, we have considered the problem of rotating, magnetohydrodynamic heat and mass transfer by free convective flow past an exponentially accelerated isothermal vertical plate in the presence of variable mass diffusion. While the temperature of the plate is constant, the concentration at the plate is considered to be a linear function with respect to time t. The plate is assumed to be...

the present article focuses on the evaluation of a first-moment closure model applicable to film cooling flow and heat transfer computations. the present first-moment closure model consists of a higher level of turbulent heat flux modeling in which two additional transport equations for temperature variance kθ and its dissipation rate εθ are considered. it not only employs a time scale that is ...

Passive phase-change thermal spreaders such as vapor chambers have been widely employed to spread the heat from small-scale high-flux heat sources to larger areas. In the present work, a numerical model for ultra-thin vapor chambers has been developed which is suitable for reliable predictions of the operation at high heat fluxes and small scales. The effects of boiling in the wick structure on...

Dissipation and flux-variance methods, derived from the turbulent kinetic energy and temperature variance budget equations in conjunction with Monin-Obukov similarity theory, were used to estimate surface fluxes of momentum and sensible heat. To examine the performance of these two methods, direct eddy correlation measurements were carried out above a nonuniform grass-covered forest clearing in...

the present work is an experimental study of steady state convective heat transfer of de-ionized water with a (0.04% by volume) volume fraction of al2o3 nanoparticles dispersed to form a nanofluid that flows through an aluminium tube.laminar fully developed flow heat transfer coefficient of al2o3 nanoparticles are dispersed in water in circular tube is discussed in this paper. in order to valid...

The Galerkin finite element method is used to solve the three dimensional continuity, momentum and energy equations for laminar Newtonian and power-law model non-Newtonian flow through horizontal circular tube. The governing equations are non-dimensionalized with respect to specific variables and converted into algebraic equations using appropriate elements. To accelerate convergence a combinat...

The Galerkin weighted residuals method is extended solve the laminar, fully developed flow and heat transfer of Al2O3-water nanofluid inside polygonal ducts with round corners for the constant heat flux and uniform wall temperature boundary conditions. Using the method, semi-analytical, closed-form solutions are obtained for the friction coefficient and the Nusselt number in terms of the radius...

In this paper the optimal control of boundary heat flux in a 2-D solid body with an arbitrary shape is performed in order to achieve the desired temperature distribution at a given time interval. The boundary of the body is subdivided into a number of components. On each component a time-dependent heat flux is applied which is independent of the others. Since the thermophysical properties are t...

The Galerkin finite element method is used to solve the three dimensional continuity, momentum and energy equations for laminar Newtonian and power-law model non-Newtonian flow through horizontal circular tube. The governing equations are non-dimensionalized with respect to specific variables and converted into algebraic equations using appropriate elements. To accelerate convergence a combinat...

Laminar mixed convection of Aluminium oxide (Al2O3)–water nanofluid flow in an inclined annulus using a single-phase approach was numerically studied. Constant heat flux boundary conditions were applied on the inner and outer walls. All the thermophysical properties of nanofluid, such as, viscosity, heat capacity, thermal conductivity, and thermal expansion coefficient...