For that study, an underfloor ventilation system providing two different airflow patterns (short and long throw) was tested and compared with a mixing and displacement ventilation system in a mock-up of a typical office. The systems were operated under identical conditions.
The authors conclude that an underfloor ventilation system providing a short throw can ensure both a high air quality (comparable to displacement ventilation), while providing a low risk of thermal discomfort for occupants.
This investigation involves full-scale experiments with two breathing thermal manikins in a room ventilated by an air distribution system based on a textile terminal extended by a personalized ventilation system . The aim is to study the improved protection of people in a room..
It appears that the flow in the room is fully mixed with a limited protection of the occupants when the air is supplied from the textile terminal alone, .and the personalized ventilation improves the protection of occupants when the personal exposure index is increased.
Correlations between indoor ozone concentrations and the emission rates of oxygenated compounds are examined in this paper. Data collected in an occupied, low-polluting office at two different ventilation rates (1 h-1 and 3 h-1) with and without common indoor sources are re-analyzed reporting that with sources present the measured total emission rate was about 5% higher at the higher ventilation rate.
The results suggest that an increased outdoor-to-indoor transport of ozone gives larger emission rates of oxygenated compounds at larger ventilation rates.
Homes with natural ventilation is a predominant type of residential buildings in taiwan . As high microbial concentrations have been reported.in those buildings, the authors have studied the effects of ventilation efficiency on indoor/outdoor levels of airborne microbes in 44 homes with natural ventilation.
Indoor and outdoor airborne bacteria and fungi were collected and the air change rate (ACH) was measured by tracer gas concentration decay method.
In pharmaceutical laboratory, the discharge of a poisonous gas by the draft chamber with high-speed responsive VAV exhaust device is necessary, but it is then difficult to maintain constant the indoor temperature. The room temperature control characteristics are analysed in that paper using CFD simulations coupled with the zone outlet temperature control simulations.
This paper compares different kinds of supply air jet that produce different air distribution in the same room. Indoor thermal comfort conditions are investigated. Measurements and calculations were made . The results were analyzed and compared to provide some valuable conclusions for application in an air-conditioned room with different kinds of supply outlets..
This paper presents two kinds of ventilation strategies applied respectively to an air-duct-type residential central air conditioning (A/C) system including a variable-speed compressor with inverter and a multi-speed air handler fan. First strategy : the ventilation damper was controlled according to the carbon dioxide (CO2) concentration of space air , allowing intermittent ventilation. Second strategy : outdoor air was inhaled into the habitable space continuously at a fixed minimum flow rate specified by ASHRAE Standard 62.2P.
A three-dimensional mathematical model is described in this paper. It intends to solve the displacement ventilation . The thermal plume and stratification of air in displacement ventilation system are clearly illustrated by numerical results. The results presented can be helpful for a better understanding and designing of this type of ventilation system.
The EPA BASE study is concerned with indoor environmental measurements in 100 U.S. office buildings. In this paper an analysis of the measured outdoor air ventilation rates is presented, it includes comparisons with the requirements in ASHRAE Standard 62
Building design and the operation strategy have an influence on ventilation and Indoor Air Quality . The unique high rise residential building design in Hong Kong is a product that complies with the Building (Planning) Regulation requirements and the request for spatial efficiency from the developers.