English

One way to prevent cold air from entering through the doorway into a building is to use an air curtain. It is a stream of air blown across the doorway that acts as a thermal barrier.

The aim of that study was to measure the performance of local ventilation for various parameter settings (nozzles and slots REEXS) and to demonstrate the benefit for real working situations.A test cabin was built, to measure the capture efficiency under reproducible cross draughts. Optimised REEXS hoods were used for the experiment : they proved to have a larger capture range compared to the conventional flanged hood. The results were so encouraging that an exhaust installation for 6 welding working places was completed.

The REinforced EXhaust System (REEXS) is a local ventilation principle for industrial ventilation with improved efficiency for capturing contaminants released by working processes .This paper discusses the validation of a 3D CFD model for the determination of the capture efficiency of standard local exhaust ventilation systems.That study has shown good results in 3 ways :- Properly designed REEXS hoods , compared to conventional exhaust devices have a significant increase capture efficiency.- CFD is an excellent tool to predict different local ventilation strategies in a quantitative way.

This paper presents the results of the performance of a wall-mounted natural ventilation convector under real winter weather conditions. The monitoring results were used as boundary conditions for CFD simulation to investigate the air movement in the test room. The results proved that the convector contributed greatly to the improvement of the indoor air quality.

A newly proposed method for evaluating ventilation performance of various types of window openings is presented with its experimental validation. The experimental system has been designed by means of wind tunnel techniques. The local similarity model of cross-ventilation is used for the application of that method.

This paper is a description of a numerical method that aims at analysing three-dimensional natural convection in rooms with wide openings.A 3D CFD tool is proposed to predict the airflow pattern and the heat and mass transfer inside a heated office room connected to a corridor via a doorway.Results have been compared to experimental data obtained in full-scale : the CFD predictions agree with the experimentally observed features.

Experimental set-up and measurement procedures were carried out to evaluate the performance of a windcatcher, using an open working section wind tunnel. Then CFD simulations were made to be compared with experimental results.The performance of the windcatcher depends on the wind speed. The wind direction also has importance

This paper is built on the hypothesis that, as the heated area increases from a point source, a displacement flow is maintained until the heated area reaches a critical fraction of the floor area, after which there is a transition to mixing flow.This hypothesis is tested in a series of laboratory experiments with the investigation of thermal stratification and flow patterns produced by a range of area heat sources located on the floor of a naturally ventilated enclosure.

Investigation by means of CFD and small-scale laboratory experiments showed that flow bifurcations could occur in building spaces ventilated by buoyancy force with large opening ceiling.A theoretical model has been developed to determine the ceiling opening size at which the flow bifurcation occurs.The predictions were in good agreement with the experimental results obtained in this work.

The first part of this paper deals with the performance of a ventilated ceiling system. Field measurements were made in a kitchen of a dietitics school in Kyoto practising mass cooking. The kitchen was half equipped with air canopy hoods to compare with the ventilated ceiling system.
A numerical simulation was conducted with CFD in order to understand the trends of the indoor thermal environment of the kitchen.