Showing papers in "International Journal of Heat and Mass Transfer in 2002"

TL;DR: In this paper, the authors explore four possible explanations for the anomalous thermal conductivity of nanofluids: Brownian motion of the particles, molecular-level layering of the liquid at the liquid/particle interface, the nature of heat transport in the nanoparticles, and the effects of nanoparticle clustering.

TL;DR: In this article, the effective thermal conductivity (ke), permeability (K), and inertial coefficient (f) of high porosity metal foams were derived by considering a circular blob of metal at the intersection of two fibers.

TL;DR: In this paper, the authors investigated the pressure drop and heat transfer characteristics of a single-phase micro-channel heat sink, which consisted of an array of rectangular micro-channels 231 lm wide and 713 lm deep.

TL;DR: In this paper, a fractal model for bi-dispersed porous media is developed based on the fractal characteristics of pores in the media, which is found to be a function of the tortuosity fractal dimension, pore area fractal dimensions, sizes of particles and clusters, micro-porosity inside clusters, and the effective porosity of a medium.

TL;DR: In this article, the effect of geometrical parameters of V-shaped ribs on heat transfer and fluid flow characteristics of rectangular duct of solar air heater with absorber plate having V-shape ribs on its underside have been reported.

TL;DR: In this paper, pressure driven liquid flow through round and square microchannels fabricated from fused silica and stainless steel was investigated and pressure drop data were used to characterize the friction factor for channel diameters in the range 15-150 μm and over a Reynolds number range 8-2300.

TL;DR: In this article, a unified two-phase flow mixture model was developed to describe the flow and transport in the cathode for PEM fuel cells, where the boundary condition at the gas diffuser/catalyst layer interface couples the flow, transport, electrical potential and current density in the anode, cathode catalyst layer and membrane.

TL;DR: Inspired by the fractal pattern of mammalian circulatory and respiratory systems, a new design of fractal branching channel net for cooling of electronic chips is studied in this article, which has a stronger heat transfer capability and requires a lower pumping power.

TL;DR: In this paper, a three-dimensional model was developed to simulate the fluid dynamics, heat transfer and phase change that occur when a molten metal droplet falls onto a flat substrate.

TL;DR: In this paper, the concept of enhancing parabolic convective heat transfer by reducing the intersection angle between velocity and temperature gradient is reviewed and extended to elliptic fluid flow and heat transfer situation.

TL;DR: In this article, a simple coordinate transformation method and the spline alternating-direction implicit method were used to analyze the rate of heat transfer for flow through a sinusoidally curved converging-diverging channel.

TL;DR: In this paper, boundary conditions for constant wall heat flux in the absence of local thermal equilibrium conditions are analyzed and the effects of variable porosity and thermal dispersion are also analyzed.

TL;DR: In this article, the authors analyzed the three-dimensional fluid flow and heat transfer in a rectangular micro-channel heat sink using water as the cooling fluid and developed a numerical code based on the finite difference method and the SIMPLE algorithm to solve the governing equations.

TL;DR: In this article, the axially-averaged Nusselt number of convection heat transfer to supercritical carbon dioxide in both horizontal and vertical miniature heated tubes was investigated.

TL;DR: In this paper, the authors reveal the inherent relation between the filed synergy principle and the three existing mechanisms for enhancing single phase convective heat transfer, i.e., decreasing of thermal boundary layer, increasing of flow interruption and increasing of velocity gradient near a solid wall, all lead to the reduction of intersection angle between velocity and temperature gradient.

TL;DR: In this paper, the authors present numerical and experimental results for buoyancy-induced flows in high porosity metal foams heated from below using a Brinkman-Forchheimer-extended Darcy flow model and a semi-heuristic two-equation energy model obtained by relaxing the local thermal equilibrium assumption.

TL;DR: In this paper, the authors measured on and above a dimpled test surface placed on one wall of a channel, and the results were given for Reynolds numbers from about 600 to about 11,000 and ratios of air inlet stagnation temperature to surface temperature ranging from 0.78 to 0.94.

TL;DR: In this article, an experimental investigation of a heat sink for cooling of electronic devices is performed based on systematic measurements of temperature, flow and pressure, infrared radiometry and high-speed digital video imaging.

TL;DR: In this paper, the delta winglet-type vortex generators are placed with a heretofore-unused orientation for the purpose of augmenting heat transfer in fin-tube heat exchanger.

TL;DR: In this paper, the steady, laminar flow and heat transfer equations are solved using a finite-volume method, and the numerical procedure is validated by comparing the predicted local thermal resistances with available experimental data.

TL;DR: In this paper, the effects of spray parameters (mean droplet size, droplet flux, and droplet velocity) on critical heat flux (CHF) were studied while these parameters were systematically varied.

TL;DR: In this article, a two-fluid model was used for predicting subcooled boiling flow at high pressure into being applicable for low-pressure conditions, and the following closure relationships or parameters are important for an accurate prediction of void fraction distributions at low pressures: (i) partition of the wall heat flux; (ii) bubble size distribution and interfacial area concentration; and (iii) bubble departure diameter and its relationship with bubble frequency.

TL;DR: In this article, the authors used a two-field model for the separate modeling of the solid and fluid phase temperature fields in a fluid-saturated porous medium, and considered how the onset criterion for convection in a horizontal layer is affected by the adoption of such a model.

TL;DR: In this paper, the authors investigated convection heat transfer in a rectangular microchannel, where the velocity profile for a rectangular channel is not known under the slip flow conditions, and the momentum equation is first solved for velocity.

TL;DR: In this article, heat transfer in the evaporator and condenser sections of a pulsating heat pipe (PHP) with open end is modeled by analyzing thin film evaporation and condensation.

TL;DR: In this paper, molecular dynamics simulations of the vaporization phenomenon of an ultra-thin layer (2 nm) of liquid argon on a platinum surface were performed, and the results reveal trends that agree with our knowledge of vaporization of a similar macroscopic system.

TL;DR: In this paper, the authors investigated the effect of ozone friendly refrigerant R-410A on saturated flow boiling heat transfer and the associated frictional pressure drop in a vertical plate heat exchanger (PHE), where two vertical counter flow channels are formed by three plates of commercial geometry with a corrugated sinusoidal shape of a chevron angle of 60°.

TL;DR: In this article, a two-dimensional heat transfer model describing anisotropic heat flow in the composite is numerically solved and a simple model is also developed to predict the heat exchange rate between the composite and the heat transfer fluid.

TL;DR: In this article, the authors present an analytical and numerical study on the heat transfer characteristics of forced convection across a microchannel heat sink, and two analytical approaches are used: the porous medium model and the fin approach.