The IAQ characteristics and the corresponding health symptoms and thermal sensation of the occupants of child care centers in Singapore under 3 different ventilation strategies are reported. The 3 child care centers studied were centrally air-conditioned and mechanically (ACMV) ventilated (Case A), naturally ventilated (Case B) and hybrid (natural and air-conditioning) ventilated (Case C).

This paper refers to the use of natural ventilation in Portuguese urban housing stock. In order to assess the goodness of natural ventilation design rules defined in a new Portuguese standard, a research project is being carried out. The results of the measurements of temperature, humidity, flow rate in ducts and weather conditions taken at an apartment in Matosinhos are presented.

Experiences from cleanroom installations has frequently shown that displacement ventilation has a much higher efficiency than mixing ventilation with respect to particle and CO2 reduction, cooling efficiency etc. Another cleanroom experience is that low particle concentration benefits asthma and allergy sufferer. Low particle concentrations reduces the impact of other pollutants and enhance the quality of life for everybody. In an office, the level of discomfort this means less tiredness, better concentration and lower absenteeism.

This paper shows the successful application of CFD simulations for analyzing complex room air flow problems in real applications and deriving optimized solutions.

The compatibility of energy conservation and thermal comfort in Japanese house with high air-tightness and insulation equipped with the whole-housing heating, ventilation and air conditioning (H.V.A.C.) system was examined by a numerical analysis. In addition to the present situation, several scenarios for achieving the compatibility were supposed. Thermal environment, thermal comfort and electricity consumption of H.V.A.C. system were analyzed throughout a year for each scenario. A combination of proper scenarios was found to be achieved the compatibility.

Isolation rooms for airborne infectious agents requires special measures to prevent air from transporting agents from the patient to surrounding rooms. This paper presents measurements for two different solutions that demonstrate that good results could be obtained by selecting construction principles that prevents air leakages and by control of ventilation airflows interlocked to door positions. Further it is estimated how different parameters influences on the transfer of infectious agents from the patient room to the surroundings.

The paper presents an extension of a two-equation turbulence model to predict the airflow fordisplacement ventilation systems. First, every flow effect is investigated separately natural convection along a vertical wall and above a person as well as mixed convection at the floor. Second, a CFD analysis of a test room is compared to full scale measurements. The modified two-equation turbulence model leads to a good agreement of the measurements and the calculations.

This paper examines airflow in rooms for a displacement ventilation system using threedimensionalCFD. A parametric study is executed for a typical office room with a dimension of 6m by 6m by 3m height according to a variety of supply air velocities, supply air temperatures and heat sourceconditions. A finite volume method and standard k- e turbulence model is employed to solve the governing equations. As a result, the temperature field in the modeled room for a displacement ventilation system is concluded according to a variety of the above parameters.

The values of the normalized concentration in the occupied zone (Cn) in an office space arecalculated by CFD for five different ventilation systems and the minimum ventilation rate which maintains the average concentration in the occupied zone under the regulated value is analyzed. Energy consumptions associated with the change in ventilation rate are analyzed. In this analysis, for most ventilation systems, the value of Cn is around 1.0, but for large circulation flow ventilation systems it changes greatly depending on the supply inlet velocity and temperature.

The distribution of the humidity in a dwelling unit is the key factor determining the condensationrisk and the mold growth, as well as the dryness problem. As the first stage of the research project aiming at the understanding and the solutions of the above problems, the experiment on humidity distribution in multiple rooms with the simulated occupancy was carried out in a full-scale research house. The effects on the humidity distribution of the ventilation, etc. are described and compared with the numerical predictions.