This study investigated the pressure flow characteristics over a number of fullscale modulated louvered windows (MLW). The various MLW parameters included louver inclination angle (8), depth (L), aperture (d) and the ratio of aperture/depth (d/L%). Airflow models were developed using both power law and quadratic model equations. By examining the coefficient of determination (r2) for both model equations, it was evident that the quadratic model equation suggested the best curves fit.
Field studies were carried out on air contamination by dust particles from air conditioning systems in four buildings in Tokyo area. We tried to investigate contamination of airborne particle and surface contamination by sedimentary dust in air duct, and considered a matter in all its aspects that caused indoor air pollution.
1. Time variations of airborne particle concentrations at supply outlet were influenced by the operation of air conditioning system.
In this study, the odor generation of various components of air handling units was investigated. Results how that air handling system really can deteriorate the perceived air quality of the supply air. Almost all components seem to be sources of pollution, but differences between the components were significant. Used fiber filters seem to be the worst. A major reason for the pollution seem to be oily, dusty, and dirty surfaces.
Ventilation systems may in some cases be a major contributor to indoor air pollution. Several studies have shown that the pollution mainly originates from the filters. Microbial growth in the filters is seen as a cause for this pollution. The sensory pollution from a standard glass fiber filter and a glass fiber filter treated to inhibit microbial growth (both EU7) were compared. No clear pattern was found in the influence of the filters on the sensory air quality. The differences between the two tested filters were not significant.
Concerning artificial ventilation of interiors, microbial processes on air filters are assumed to cause pollution of the supply air with possible damage to the exposed persons' health. Therefore, the reaction of microorganisms on air filters was analysed in this project. The analysis focused on the influence of air temperature, relative air humidity, the filter medium and service life as determinants for microbial growth on air filters. The experiments showed that the parameters air temperature, filter medium and service life had no significant influence on microbial growth.
Recent concerns have been expressed with regard to emissions of glass fibers from heating, ventilation, and air conditioning (HV AC) systems. In this literature review, over 350 citations were found, of which 10 reported original measurements of glass fiber concentrations associated with the presence of fibrous glass duct lining or duct board, and two yielded sufficient data from which emission rates could be calculated.
Passive solar cooling for hot humid areas represents an important field for innovation, if we want to solve comfort needs in spaces (especially housing) designed to reduce economic, technical and health requirements. In urban areas or deep valleys and rain forests, which are common in most of the tropical equatorial countries, external breeze is not frequent and air speeds are too low to produce cooling, using a simple cross ventilation system. Since 1982 the author has developed new designs and constructions using passive solar techniques.
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