The objectives of the present work are to use computational fluid dynamics (CFD) to studythe airflow pattern and to evaluate the effectiveness of the passive cooling design of theproposed Jurong General Hospital (JGH) using natural wind. The complex three-dimensionalCFD model is used to assess the environmental conditions at the deep podium inside the JGHcomplex with prevailing wind conditions in Singapore, corresponding to the monsoon(November-February) and hot (March-October) seasons.

Tracer gases are often used to assess airflow rates in air handling units. Published methods aremostly designed for units with recirculation ratios lower than those commonly found inSingapore and other tropical countries. Large recirculation ratio homogenize theconcentrations, so that concentrations in supply and extract ducts are close to each other. Inaddition, such units often present a large time constant, so the time needed to reachequilibrium is very large. A procedure for tracer gas dilution technique adapted to such airhandlingunits is presented.

School indoor air quality has become of concern recently in Korea. In this paper, it is intendedto investigate the ventilation performance and thermal comfort characteristics of a classroom,when an outdoor air system is installed in addition to a ceiling-mounted heat pump system.Experiments were conducted in a full-scale model classroom to collect experimental data tovalidate numerical schemes. Three-dimensional temperature distributions were measured withthermocouples distributed throughout the space, and ventilation effectiveness was measuredusing a tracer gas technique.

This paper presents the indoor air quality performance of a displacement ventilation system ina thermal chamber. This study consists of two sets of experiments. In the first experiment, thethermal chamber was operated under displacement ventilation (DV) mode with the relativehumidity (RH) set at about 65% while the ambient temperature (AT) at 1.3 m height variedfrom 22 to 26C. In the second experiment, all the conditions are the same except that theventilation strategy is changed to mixing ventilation (MV).

Earlier studies have shown that airflows are not well balanced in office buildings. This maylead to too low ventilation rates in some rooms and too high ventilation rates in others.Several studies have shown that low ventilation rates may lead to a higher prevalence of SBSsymptoms. The reduction of these symptoms may be achieved with improved ventilation.The purpose of this study was to evaluate the benefits of balancing the airflows of the airdistribution system of an office building in Helsinki.

In order to effectively control nosocomial infection 12 respiratory isolation rooms fortuberculosis patients in four hospitals have been built by the Energy & Resources Laboratories,Industry Technology Research Institute in Taiwan. This project was funded by the Center ofDisease Control of the Health Department. The performance of the air-conditioning andventilation/exhaust system of respiratory isolation rooms has been tested and validated. Thetested items include ventilation rate, static pressure, temperature, humidity and noise.

The efficacy of a natural ventilation strategy is essentially conditioned by the sizing ofcomponents on which the airflow control depends. The indoor environment conditioning issubmitted to strict regulation. The implementation of the natural ventilation strategy is relatedto the building layout; therefore, the devices sizing is important for the architect. On the basisof the loop equation proposed by James Axley, we developed a simple sizing tool.

There is an increasing evidence of air related sickness among infants and housewives in urbanIndia due to the use of liquefied petroleum gas. An attempt has been made in this study, tomonitor kitchens of 13 houses in the city of Jaipur for possible residential indoor air pollution(IAP), i.e. carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2) and respirablesuspended particulate matter generated during cooking. The role of the exhaust fan as aninexpensive means to dissipate these gases of combustion has also been studied.

The paper will discuss design models for the air distribution system in an office with twopersons. The comparisons are made between mixing ventilation and displacement ventilationand they are based on a maximum velocity assumption and a restricted vertical temperaturegradient in the room. The comparison is extended by considering both the local discomfortcaused by draught rating (DR) and the percentage of dissatisfied due to the temperaturegradient (PD).

Studies have documented that personalized ventilation, which provides clean air at each officeworkplace, is able to improve substantially the quality of air inhaled by occupants. However,the interaction between the airflow generated by personalized ventilation and the airflowpattern outside the workplaces has not been studied in detail. This paper presents a study onthe performance of a personalized ventilation system installed in a full-scale test room with anunderfloor air distribution system.