The heat transfer coefficient value strongly depends on surface temperature rise and cooling fluid velocity. Thus, taking into account that usually large temperature gradients occur in air cooled electronic circuits, the local values of this coefficient might differ substantially throughout circuit outer surfaces. Consequently, the assumption of heat transfer coefficient uniformity for the enti...

Three-dimensional simulations of condensation of refrigerant R134a in a horizontal minichannel are presented. Mass fluxes ranging from 50 kg m -2 s -1 up to 1000 kg m -2 s -1 are considered in a circular minichannel of 1 mm diameter, and uniform wall and vapour-liquid interface temperatures are imposed as boundary conditions. The Volume of Fluid (VOF) method is used to track the vapour-liquid i...

In this paper the steady laminar magneto hydrodynamic (MHD) mixed convection boundary layer flow towards a vertical stretching sheet with variable fluid viscosity, radiation and in the presence of Dufour’s effect have been investigated. The governing partial differential equations are transformed into set of ordinary differential equations using similarity transformation, and then these equatio...

During dropwise condensation from vapor onto a cooled surface, distributions of drops evolve by nucleation, growth, and coalescence. Drop surface coverage dictates the heat transfer characteristics and depends on both drop size and number of drops present on the surface at any given time. Thus, manipulating drop distributions is crucial to maximizing heat transfer. On earth, manipulation is ach...

Nomenclature a = stoichiometric coefficient av = surface-to-volume ratio C;, Cb; = surface and bulk concentration, vol % Da = Damkohler number Eif R = activation energy, K F = steady-state function h = heat-transfer coefficient K, = adsorption equilibrium coefficient k, k0 = reaction rate constant and preexponential factor, respectively kc = mass-transfer coefficient l = apparent reaction order...