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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.

Tracer gas sorption in and permeation through building materials influence tracer gas ventilationmeasurements. Therefore, it is important to have knowledge about these processes.The permeation of three commonly used tracers (SF6, N2O and the PFT C6F6) through untreatedgypsum board has been experimentally investigated. The result shows that all three tracers diffusereadily through this material (diffusion coefficients in the order of 1 10.-6 m2/s). Caution shouldtherefore be exercised when using tracer gas measurements in rooms with walls of gypsum boardor other porous materials.

Ventilation is the most effective procedure to reduce indoor air pollutant. Volatile organiccompounds (VOCs), which cause health related symptoms, are often detected in the indoorenvironment. The way of ventilation should be decided depending on the level of VOCs. Thelevel of VOCs and ventilation rate are usually measured individually. This study will proposea simple method to measure both the ventilation rate, by perfluorocarbon tracer gas technique(PFT), and VOCs concentration immediately by using a single sampler.

Natural ventilation is a prevailing way to relieve the indoor thermal environment against warmand humid climate. The field measurement of the thermal performance of a model house withnaturally ventilated double skin walls compared with a conventional insulated model housewas carried out. Only the gap between the double skins is ventilated, while the indoor of theconventional model is ventilated mechanically.

This paper describes the unsteady terminal and presents its characteristics gained fromexperiment. The experimental results showed that the fan-coil unit tested in the experimentwas able to provide fluctuating airflow and the velocity curve of supply airflow wasconsistent with the control signal very well. The spectrum of supply airflow is similar to thespectrum of natural wind if the control signal simulating natural wind provided. The supplyair temperature is changed when the airflow is changed.

Mixing ventilation and displacement ventilation were compared in an intervention study inclassrooms. Particles, cat allergen and CO2, were measured in classroom air at different levelsabove the floor, during regular lessons. With mixing ventilation, the particle concentrationtended to decrease with height, with a stronger gradient occurring for larger particles. Withdisplacement ventilation, the particle concentration increased with height, except for particles>25 m. The displacement system thus tended to have a slight upward displacement effect onmost of the particles.

The thermal environment in vehicles varies greatly. The interaction of the cabin thermalenvironment, created by the HVAC system, the outdoor conditions as well as the occupants,is rather complex.In this regard, in order to improve occupants comfort, we thought of locally differentiatingthe parameters which influence peoples satisfaction.