English

In this paper, the normal ventilation system and the concept of all fresh air conditioning and ventilating system are presented. The 2 systems are then compared, with the use of a non-isothermal k-e turbulence model.Results show the wind velocity distribution , the temperature distribution and the Scale for Ventilation Efficiency distribution for each case.Their conclusion is that with the all-fresh air ventilation system, there is a high ventilation efficiency around the occupant zone.

In general, there are 3 locations used for the fresh air supply in a standard cleanroom : under the ceiling of supply air plenum, at the return air shaft, and under the raised floor. In this study, the influences of the three different fresh air supply locations on field velocity and temperature distributions of fan filter unit are investigated then compared. The airflow distribution is simulated by the standard k-e turbulence model. Results are presented and discussed..

The Volatile Organic Compounds concentrations in indoor air tend to be higher than the level allowed by the standards or codes. Photocatalytic oxidation by employing UV radiation is a promising approach for the VOCs removal .The purpose of this paper is the development of a simple but effective model of photocatalytic oxidation air cleaner.With that model, the design and the selection of suitable photooxidation air cleaners and the measurement of their Volatile Oragnic Compounds removing effect can be easily conducted..

This paper deals with the use of an Air Curtain Device in a typical HVAC application where there is a need to provide aerodynamic sealing between a comfortable human enclosure and a warmer neighbour space.Three different complementary experiments were used in this work : tracer gas method (N2O), Flow field mapping and Infrared thermo-graphic visualizations.The used experimental methods revealed adequate and complementary to understand the flow topology of the studied case

Emissions due to chicken farming should be minimised because they increase the greenhouse effect on the one hand and odours lead to annoyance. This paper sums up the investigations conducted in various chicken houses to analyse the effect of drying the chicken manure. The emissions streams were measured in different sites with tracer gas (SF6 or Krypton 85). Thanks to suitable ventilation systems the manure can be dried and thus ammonia and odour emissions streams can be purposefully reduced.

A validated CFD model was used to generate concentration distribution data for CO2, radon and moisture in a Hong Kong workshop with displacement ventilation.Contaminant concentration distribution depends on the contaminant source type and location. A low concentration may be obtained in the occupied zone when the contaminant source is associated to a heat source whose thermal plume is sufficiently strong to reach the upper zone.

The objective of this paper was to illustrate the potential of the CFD technique to compare the effectiveness of different general ventilation systems in reducing the workers' exposure to styrene vapour in a workroom. . Thanks to the CFD technique predicted airflow velocities and styrene distribution are shown for the 3 different ventilation arrangements at identical planes across the room. And predicted values of styrene concentration at workers'position are given.

2 examples of extract systems are presented in this paper : the first one concerns dust removal in a public waste plant and the second smoke separation in a smoker/non-smoker zone with no visual impact (i.e. no walls).Thanks to the CFD simulation, proper exhaust systems for dust and smoke have been successfully designed and optimised for each case with simulation results. The proposed solutions were then realized and with few minor modifications led to excellent working conditions on the one hand and excellent smoke caption on the other hand.

The thesis deals with human perception of the environment, sick building symptoims and the performance of office work in the indoor environment. Single and combined effects of temperature, heat stress, noise and air quality have been studied in three experiments.

This guide describes the principles of demand controlled ventilation, gives information about the type of buildings where it can be used, and underlines the benefits of such systems with regard to energy consumption. It also shows how to design a demand controlled ventilation system according to the type of control. It explains the importance of choosing the right type of sensor and the correct way to posiiton it in the room.