Variations in heat source positions in a room bring changes in the ventilation effectiveness. Those changes are studied using experimental data and CFD results. Results show that a good ventilation effectiveness can be achieved when the contaminant and the heat source are located close to the zone containing the exhaust opening.
The concentration of fungal spores is higher in the crawl space than inside houses. Domestic mechanical exhaust ventilation systems may create air flow between crawl space and base floor through leaks. This study used data from eight buildings to develop a model providing relation between indoor and crawl space fungal spores concentrations. Results show that the correlation between the fungal spores in the crawl spaces and indoors depends on the size range of microbe species.
In an air-conditioned office building in Singapore, 3 different filtration systems have been evaluated under similar fresh air intake and ventilation rate conditions (electrostatic filtration, electrostatic filtration with chemical adsorption, and media filtration) . Chemical and microbial contamination levels under different filtration strategies have been monitored.
A method for analyzing the thermal and lighting radiations in offices building has been developed. It enables the simulation of complicated lighting environments composed of a combination of artificial lighting and solar radiation, in ventilated and air conditioned offices.
This paper describes a method for the determination of optimal indoor conditions, using three parameter indexes: PMV (predicted mean vote) for thermal comfort, CO2 concentration for indoor air quality and cooling/heating load for efficient use of energy. A performance index of the HVAC system is calculating by adding square errors between actual and desired values. It is then minimized to find optimal indoor air conditions.
This paper deals with the simulation of air flow pattern in an office in Singapore (22.5 m x 84 m) with a typical day environmental conditions. Thermal comfort and indoor air quality audit, as well as ventilation measurements are used for validation of the simulation results.
In 2 tropical countries such as Singapore and Indonesia, the perception of thermal comfort is different for people according to their living standards. The higher the standard of living is, the better comfort in living environment is required. A comparative study has been conducted with subjective and objective measurements.
Two methods have been used for measurement of natural convection flows in a narrow vertical channel of which one wall is heated : a hot wire anemometer adapted to measurements in flows where temperature gradients exist (two hot wires with different overheat) and a method for attaining bulk flow information in boundary layer flows. Results from these two methods are compared.
Guangdong is one of the provinces that have most hot springs in China. This paper presents the results of radon measurements in hot spring hotels of Guangdong province by using NR-667A continuous radon detector. Radon concentrations were measured in hotel rooms with attached bathrooms, tap waters and outdoors air. Radon concentrations were 53.4-292.5 Bq/L in the hot spring water, and 17.2-190.9 Bq/m3 in outdoor air.
Provision of good IAQ in buildings located close to a busy road requires application of air filtration systems which are efficient for submicrometer and especially ultra fine particles, since traffic emissions are associated with particles in these size ranges. A study has been conducted in which a filtration system of an office building was designed according to measured outdoor air conditions and theoretically predicted indoor air conditions. The performance of the system was then validated by field measurements of particle concentration levels indoors and outdoors.