A CFD code has been used to design and optimize the ventilation system of a building dedicated to auto-racing (120 000 persons, 45 cars). The constraints are the dimensions of the building, the heat and pollutants due to cars, their high speed and the size of granstands. The article shows the interest of airflow modeling to study the complex ventilation system of such a building.
Experiments and calculations were operated to determine air flow distribution in a test room (9.9 m2) naturally ventilated through adjustable louvers overlooking outside. Air enters at the bottom (opening surgace 0.07 m2) and is exhausted at the top of the room (opening surface 0.12 m2). Air pressure and velocities across the opening allow to estimate wind pressure coefficients. Results show in particular the influence of wind on the internal air flow. Good agreement was found between measurements and calculations.
A two-dimensional particle image velocimetry (PIV) technique was used to measure velocity and turbulence of air flow around a heated manikin in a large room (volume about 80 m3). Measurements were operated in four horizontal and ten vertical planes. The article describes the PIV system and the type of results which were obtained.
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.
This paper gives formulas for optimal design of all-air systems regarding costs, allowing to calculate the optimum outdoor air rates in office buildings.
Tests have been performed on several ceiling air diffusers supplied with low air temperatures (6 to 16°C - 90% humidity) to study water vapour condensation on diffusers surface. Results show that a supply air temperature of 11°C avoids most of condensatio
Detailed testing of multi-zone airflow and ventilation rates in a dwelling were conducted using two different types of tracer gas method and compared with design.
A study was done to obtain a general understanding of the mechanisms involved in the emissions from building materials in ventilated rooms. The investigation was based on fundamental fluid dynamics and mass transfer theory. Also proposed a generally applicable method for the prediction of surface emissions. No particulate emissions were analysed, and the work focused on the emission of vapours and gases. Numerical calculations by CFD and full-scale laboratory experiments were used.
Describes a case of primary and secondary infections of TB in an office environment in Tokyo, Japan. It was found that the ventilation system was frequently closed down to save energy, resulting in high CO2 concentrations. Concludes that the secondary infections were due to insufficient ventilation.
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