convective heat transfer

An Earth-to-Air Heat Exchanger (ETAHE) uses the ground’s thermal storage capacity to dampen ambient air temperature oscillations by delivering the outdoor air to the indoors through a horizontally buried duct. Most ETAHE simulation models assume the airfl

An Earth-to-Air Heat Exchanger (ETAHE) is a low energy cooling and heating technology for buildings. It uses the ground’s thermal storage capacity to dampen ambient air temperature oscillations by delivering outdoor air to indoor through a horizontally bu

The buoyant plume characteristics of heat sources and their relation to geometric factors are of fundamental importance to the effectiveness of the displacement ventilation. The interactions in buoyant plumes from an array of horizontal line heat sources are investigated systematically with Mach-Zehnder interferometer. Based on the discussion about convective flow patterns of a single lime heat source, the characteristic velocity and temperature to character the accumulating buoyancy effects of an array of horizontal line heat sources are proposed.

This paper deals with the convective flow through a horizontal aperture connecting two superimposed large enclosures which are kept at different temperatures. The lower room is warmer than the upper room and this unstable thermal configuration generates a natural them1osyphon flow, between both volumes. This type of flow can occur inside buildings: stairwell flows or natural ventilation flows through horizontal openings. In the literature, very little information is available concerning this domain of applications.

The purpose of the presented investigation is the comparison between measured data of the laminar and turbulent mixed convection and their approximation by wall functions. New wall functions were implemented in a FVM-research-code using unstructured grids, which was developed by the author. Numerical results are compared with a turbulent closed cavity flow.

This study is a part of a research project named 'Convective Flows and Vertical Temperature Gradient within Active Displacement Air Distribution'. The project was started in 1996 in order to determine guidelines for air flow rate dimensioning of the system. Aim of this study was to determine the characteristics of the thermal plumes of the heat sources used in the project. The characteristics were determined in order to apply the results to different kinds of plumes, which may occur with active displacement air distribution system.