Showing papers in "International Journal of Heat and Mass Transfer in 1994"

TL;DR: In this paper, a numerical simulation of forced convective incompressible flow through porous media, and the associated transport processes was employed, and a full general model for the momentum equation was employed.

TL;DR: In this article, the authors examined the local heat transfer characteristics of air jet impingement at nozzle-plate spacings of less than one nozzle diameter using an infrared thermal imaging technique.

TL;DR: In this article, an experimental study of pressure drop and CHF in mini-channel (D = 2.54 mm ) and micro-channel heat sinks of 1 cm heated length was performed using R-113.

TL;DR: In this paper, the authors investigated the single-phase forced-flow convection of water or methanol flowing through microchannels with rectangular cross-section and found that the fully developed turbulent convection regime was initiated at about Re = 1000-1500.

TL;DR: In this paper, the authors studied microscopic energy deposition and transport processes during short-pulse laser heating of multi-layer metals: absorption of radiation energy by free electrons and energy exchange between electrons and the lattice.

TL;DR: In this paper, an experimental study using a suspension of n-eicosane microcapsules in water was conducted in order to evaluate the heat transfer characteristics of phase change material suspensions.

TL;DR: In this paper, the effects of jet-jet spacing, low nozzle-plate spacings, and spent air exits located between the jet orifices were studied on the magnitude and uniformity of the convective heat transfer coefficients for confined 3 × 3 square arrays of isothermal axisymmetric air jets impinging normally to a heated surface.

TL;DR: In this article, the transfer of chemically reactive species in the laminar flow over an elastic plane surface is considered, and the viscous flow is driven solely by the linearly stretched surface and the reactive species is emitted from this sheet and undergoes an isothermal and homogeneous one-stage reaction as it diffuses into the surrounding fluid.

TL;DR: In this paper, a modified Zehner-Schlunder model is proposed for calculations of the stagnant thermal conductivity of two types of porous media with spatially periodic structures, where the area-contact model is developed to take into consideration finite area contacts between spheres in a packed-sphere bed.

TL;DR: In this paper, the authors performed femtosecond thermoreflectivity experiments to investigate energy deposition and transport during the very early period of short-pulsed laser heating of gold and chromium multi-layer metal films.

TL;DR: In this article, the authors presented numerical investigations of the flow structure and heat transfer enhancement in a channel with a built-in circular tube and a winglet type vortex generator and showed a marked increase in overall channel heat transfer.

TL;DR: In this article, the critical heat flux (CHF) of subcooled flow boiling was analyzed based on the liquid sublayer dryout mechanism, i.e. the dryout of a thin liquid layer beneath an intermittent vapour blanket due to the coalescence of small bubbles.

TL;DR: In this paper, the authors used a charge coupled device (CCD) camera and flow regimes were determined by examining the video images, and a comparison of the resulting data was made with previous experimental data and also to existing transition criteria.

TL;DR: In this article, heat transfer between a uniformly heated flat plate and an impinging circular air jet was investigated experimentally to determine the values of the local and average Nusselt numbers, particularly for small values of Reynolds number and jet spacing.

TL;DR: In this article, an experimental study of forced convective subcooled boiling heat transfer to water was performed at heat fluxes that ranged beyond 10 8 W m −2, and the predictive ability for the critical heat flux (CHF) at high heat flux was obtained.

TL;DR: In this article, the Nusselt number was observed to correlate approximately with Re 0.5 and Re 1.8 for initially turbulent and laminar jets, respectively, for both free-surface and submerged jet configurations.

TL;DR: In this article, a model for heat transfer in composites in the presence of interfacial thermal resistance is determined from a description at the heterogeneity scale using a method of double-scale asymptotic developments.

TL;DR: In this paper, a two-dimensional heat pipe transient analysis model, called HPTAM, is developed for simulating operations of fully-thawed heat pipes, where the axial distributions of liquid and vapor pressures, effective radius of curvature of the liquid meniscus at the liquid-vapor interface, and liquid pooling and recession following step function heatup and cooldown transients of a horizontal water heat pipe.

TL;DR: In this paper, a very small film heater immersed in ethyl alcohol, toluene or water is heated at an extremely high rate to a maximum temperature rise of 93 × 106 K s−1.

TL;DR: In this article, the authors developed a correlation of the following form: Nu = AF(p) Re 0.67 b Pr 0.4, where Nu is a function of the critical pressure alone, F(p), F (p), and Re b is based on the mean vapour mass flux from the surface and the tube diameter.

TL;DR: In this article, an analysis of available correlations and models for the prediction of critical heat flux (CHF) in subcooled flow boiling in the range of interest of fusion reactors thermalhydraulic conditions, i.e. high inlet liquid subcooling and velocity and small channel diameter and length, is presented.

TL;DR: In this paper, a long heating test section (627 diameters) with a uniform heat flux boundary condition is constructed in order to study the effects of the phase change phenomenon produced by a phase-change material (PCM)-water slurry on the convective heat transfer coefficient in a turbulent flow.

TL;DR: In this paper, the effect of the volume-averaged conservation equation on the flame structure and speed in adiabatic, premixed methane-air combustion in porous media is examined.

TL;DR: In this article, the integral transform method is reviewed as a benchmark tool in computational heat and fluid flow, with special emphasis on nonlinear problems and the hybrid numerical-analytical nature of this approach collapses the numerical task into one single independent variable, and thus allows for a simple computational procedure with automatic global error control and mild increase in computational effort for multidimensional situations.

TL;DR: In this paper, performance evaluation equations for enhanced heat transfer surfaces based on the entropy production theorem are reported, which originate from various design constraints and generalize the performance evaluation criteria (PEC) obtained by means of first law analysis.

TL;DR: In this paper, an experimental study has been made on steady state natural convection heat transfer from vertical helical coiled tubes, where average heat transfer coefficients were obtained for turbulent natural convections to water.

TL;DR: The study shows that genetic algorithms allow a cost-effective approach for investigating highly complex numerical and/or experimental thermosciences problems where it is desirable to obtain a family of acceptable problem solutions, as opposed to a single optimum solution.

TL;DR: In this article, the influence of wall heating condition on the local heat transfer coefficient in a rotating, two-pass, square channel with 90° transverse ribs on the leading and trailing walls was investigated for Reynolds numbers from 2500 to 25000 and rotation numbers from 0 to 0.352.