English

The paper gives an explanation of the phenomenon of attachment of a cold air jet to a ceiling, based on a theoretical analysis. A formula to calculate the distance between the blowing slot and the point where the cold air jet will separate from ceiling is given. The results of calculations using this formula show good agreement with experimental data.

The market evolution of domestic exhaust air heat pumps since 1979 in Sweden is described. Some information is also given about the German market. Technologies of different exhaust air heat pumps systems are shown and results of several monitoring projects in Sweden are summarized : they show for houses built in the 1980's an electricity consumption of 90 to 130 kWh/m2/year (including domestic hot water and household electricity), depending on the thermal characteristics of the building envelope. The energy savings thanks to the exhaust air heat pump are about 30%.

The revision of Ashrae standard 62, Ventilation for Acceptable Indoor Air Quality, began in 1991. This article gives a summary of the changes that have been approved and describes the issues that remain to be resolved.

Describes the content of the European and International standard EN-ISO 13792 which allows the simplified calculation of the internal temperature in hot season of a room without mechanical cooling.

The article presents the scope and content of ISO 13790 standard which is intended to calculate the energy use for space heating of buildings. Information is given about the accuracy of the standard calculation method.

Field measurements were carried out on six office buildings in Taïwan to evaluate ventilation efficiencies on the concentration of formaldehyde and TVOC, as well as the impact of ventilation rates on reducing these concentrations.

This paper gives formulas for optimal design of all-air systems regarding costs, allowing to calculate the optimum outdoor air rates in office buildings.

This study is to validate a CFD model of displacement ventilation combined with chilled ceiling and determine if this combination may create draught risk or influence badly indoor air quality.

A CFD code was used to study an office equipped with a radiant cooled ceiling and a wind-induced cross-ventilation system. Calculations covered several heights of the ceiling.

A procedure to verify, validate and report CFD analyses in indoor environment applications has been developed. The process on how to use this procedure is explained through the example of CFD modeling of an office with mechanical displacement ventilation.