There is a relationship between geometric room parameters and the air flow patterns produced by mechanical ventilation systems. Experimental measurements of indoor air flows in a one-tenth sub-scale model room were made and compared to numerical simulations. The results show how obstructions can influence the air flow and contaminant transport in a room.
This paper presents the results of a field study on five HVAC duct systems in France. The principal objectives of this work were a) to evaluate the extent of duct leakage in those systems; b) to compare design and actual fan flow rates; c) to evaluate the thermal energy losses in the air ducts. The ductwork airtightness, measured by fan pressurisation method, was found to be in general well above the leakiest EUROVENT 2/2 class (class A), yielding unacceptable uncontrolled airflows. Fan airflow rates were measured with the constant injection tracer gas method.
In the introduction of the paper are reasons presented, which cause local thermal discomfort. Currently the reasons of asymmetric thermal radiation are not clearly explained. Therefore I oriented my experimetal laboratory measurements, which were carried out in a special microclimatic laboratory on radiant ceiling heating. A special laboratory model of heating of interior was created. The measurements were performed with the help of a thermal mannequin that was used to measure the asymmetric radiation (that is asymmetry of perceived temperature).
The main objective of our study was to know more about indoor air quality in offices building over a long period. Our study has been carried out in one building located downtown Lyon (France). Measurements have been carried out one day each month during a one year period. Indoor air quality in the offices along with the one of air flows of the HVAC (Heating, Ventilating and Air Conditioning) installation (outdoor air, blown air and returned air) has been characterised by temperature and relative humidity of air, dust concentration level, air biocontamination and CO2 concentrations.
Measurements of wind speed and wind direction, air temperature inside and outside an urbancanyon also infrared radiation in buildings have been measured on summer 2001 in Athens, in fivedifferent urban canyons, in the frame of Urbvent project. Urban canyons with different geometricalcharacteristics and orientation were placed in five different neighborhoods in Athens.Measurements took place in four different height levels inside each canyon, in the facades ofthem, also in the top of each canyon.
This study investigates the behavior of vapor in a ventilated room in which vapor is being produced. A test chamber equipped with three types of ventilation ducts and a vessel filled with heated water for evaporation was analyzed both experimentally and numerically. Experimental results showed that temperature and moisture distributions differed depending on the ventilation types. A numerical model of vapor generation from the heated water was introduced to simulate the evaporation.
Ventilation is one of the most important measures to dilute indoor air pollutants. In order to maintain a clean indoor air environment, not only the total ventilation rate of the building but also the distribution of outdoor air to each area must be taken into consideration. A performance evaluation of the combined system of air supply from the crawl space and hybrid exhaust ventilation with a small fan and damper has been investigated. This investigation was undertaken over a heating season using a full-scale test house.
In conventional construction, the ventilation air enters a building through a combination of ‘desired’ pathways, via opened apertures, such as a window, vents, and ‘undesired’ pathways, via cracks such as around external openings, joints between building
Detailed simulation studies on the design and development of PV/T systems are being carried out at the Politecnico di Milano, for their possible integration with a sloped roof. Subsequently, a proto-type PV/T air heating collector has designed, manufactured and tested at the experimental site Parco Lambro in Milan in collaboration with a private industry. Thermal and electric efficiencies have been assessed during several days of experimentation.
Double skin façades may help combine a high degree of transparency with high thermal and solar performance. Advanced façades serve as filters and may be responsive to changes in environmental conditions and occupant requirements. Since the strategies for
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