English

Ventilation requirements for vehicular tunnels in the Hong Kong Special Administrative Region are discussed. For vehicle emissions, carbon monoxide is considered to be important for vehicles running on petrol engines, and suspended particulates for diesel engines. Other environmental control parameters are temperature, air speed and air pressure. Codes, regulations and design guides for ventilation systems are reviewed. Different ventilation designs adopted in local vehicular tunnels are described.

The effects on pressure loss of the separation and orientation of closely coupled duct fittings in RVAC systems were investigated using computational fluid dynamics to analyse the pressure distribution in a system containing two 90° bends in two common configurations; an S bend and a U bend. Fittings that are separated by less than 8 to 10 hydraulic diameters· of the duce behaved in very different ways depending upon the orientation of the fittings in relation to one another.

19 university students were asked about their thermal comfort while attending ordinary lessons in a displacement ventilated test room of typical classroom size. Two different ceiling heights were tested. Both the general temperature level and the strength of the vertical temperature stratification in the room increased continuously during the lessons due to the presence of the students, however slower with the higher ceiling.

Researches into natural ventilation characteristics of courtyard buildings have been carried out extensively in climates very different from tropical climate. Nevertheless, courtyards have been incorporated for centuries in traditional shop houses and also adopted in many modern commercial buildings in tropical countries such as Singapore. This paper discuses a study to investigate the natural ventilation characteristics of courtyard buildings in Singapore. Four typical courtyard buildings are examined.

This paper describes an investigation into the ventilation performance and the indoor air quality of a portable classroom. Both field measurements and numerical simulations based on CFD (Computational Fluid Dynamics) technology were used. Field measurements in an unoccupied classroom used smoke to visualize the flow pattern, and hot-film probes to quantitatively measure air velocity. These field measurements provided the boundary conditions for CFD simulations and the experimental data to examine the accuracy of the CFD simulations.

Habitat for Humanity affiliates and other low-cost builders can achieve annual space conditioning costs of less than $250 per year through inexpensive envelope measures and equipment 'downsizing.

The light well is often designed in the center of high-rise apartment buildings in Japan. This light well is an empty space without ceilings or floors from the bottom to the top, and this well is called "Void" in Japan. In this well, the exhaust from the kitchen and the gas water heater is sometimes discharged to the corridors surrounding Void, and the exhaust can pollute the air in Void. To keep the air quality in Void clean, the natural ventilation is usually depended on.

The focus of this paper is on controlling ventilation rate to provide acceptable temperature and relative humidity in the space being ventilated. To this end, a system of heat and moisture balance equations for building indoor and components is described. The system is solved numerically. Based on a series of indoor temperature and moisture measurements for our experimental house and well-mixed air distribution in room, moisture generation rate is estimated. The model is validated by simulating the experimental house. Good agreement between the simulated and measured results is obtained.

Because of the lack of valid information regarding the influence of bends on the thermal and hydraulic performance of flues, a series of preliminary experiments were conducted using a full-scale Perspex rig. Analysis of the results and observations enabled the development of a methodology capable of determining the reduction of flow rate arising from the presence of bends. The analysis has also shown that existing quasi-steady-state methods used for the design of these flue systems are valid.

This project has studied a selection of 16 typical museums for antiquities in five Mediterranean countries and was partly funded by the JOULE III of the European Commission DG XII. Through an elaborate analysis and complete refurbishment of the Archaeological Museum of Delphi, the programme has provided an example for an innovative museum design based on present-day know-how.