Air distribution solutions for classrooms aiming to lower air velocities and good temperature control are studied by measurements in 6 schools and temperature simulations. Air velocity measurements showed good performance of duct and ceiling diffusers which provided maximum velocities less than 0.2 m/s and can be highly recommended for classrooms. The wall diffusers were clearly not suitable for classrooms due to high velocities up to 0.43 m/s.
Many research papers have been published on the potential effects of the quality of the indoor environment on productivity in classrooms and offices. This paper (Part 3) reports the result of nationwide field measurements based on subjective questionnaire surveys and objective test scores in a unified way.
The purpose of the present paper is to investigate the effect of outdoor weather conditions on the performance of a plate-type heat recovery ventilator. The performance should not be affected in a theoretical point of view. However, the performance varies in real applications, because of air leakage, motor heat generation, and etc. Experiments have been conducted to measure the sensible, latent, and enthalpy efficiencies by varying outdoor temperature and humidity conditions with the indoor conditions fixed at the standard heating or cooling conditions.
This paper analyses the problem of improving the performance of the mass transfer withthe standpoint of field synergy theory. It mainly studies with the view that adjusting an angle between velocity field and density field could enhance the performance of dehumidifying air-conditioner. At the same time, it cites one kind of the structure of screw type beehive wad dehumidifying airconditioner and screw baffler dehumidifying air-conditioner which is fixed with an angle, validates its performance of intensifying mass transfer and discusses the extensive applications in engineering.
The purpose of this paper is to investigate the thermal performances and the effect on the thermal comfort of a cooling ceiling installed in an experimental test room called Minibat. With a 9.6m2 surface and controlling the temperatures on all the exterior walls of the cell, Minibat was the perfect environment for this experimental study. The studied ceiling panels were equipped with capillary mats using polypropylene as material. During the experiment we have analyzed different cases where the ceiling surface temperature varied between 15C and 19C.
Heating, ventilating and air-conditioning (HVAC) system sizing for existing single family residents in hot and humid and temperate climates present different problems. In hot and humid climates, the proper sizing of residential air-conditioning systems is an important issue, since if the system is over-sized the resulting mold problems can cause significant problems with occupants who are susceptible to airborne spores like mold that can severely affect their asthmatic illnesses.
This study was carried out in collaboration with the district heating firm RADET SA from Bucharest, Romania, in order to support the acoustic renovation of the thermal stations, to meet the modern requirements of the indoor acoustic comfort. The measurement sequence consists in the recording of the sound pressure level in a bloc of flats: inside the thermal station placed at the underground level of the building and inside the apartments. The noise level was 70 dB inside the thermal station and over 44 dB inside the apartments.
An epidemiological cross-sectional questionnaire study on housing and health, involving 229 children in Sisimiut, was initiated in May 2006. Based on this study, a nested case-control study was carried out in August 2006, covering inspections and physical measurements in the homes of 51 children. A tendency towards a lower average CO2-concentration in the bedroom, at night, in the group of sick children (cases) compared to the group of healthy children (controls) was found.
The aim of this project was to investigate the indoor environment and building characteristics in relation to with asthma and allergy among Greenlandic children. A cross-sectional questionnaire study involving 229 children in schools and institutions in Sisimiut was performed. The response rate was 23%. Of the children included,15% had doctor-diagnosed asthma. Rhinitis and eczema within the last 12 months was associated with; visible damp stains in the childs room; mouldy, earthy, unpleasant and tobacco smell and with suspected dampness in the construction.
Clean indoor air is one of the most important factors for the welfare of the society. To understand and study the complex causality of different factors affecting indoor air quality, a databank and an IAQ-simulator have been developed. Databases have been developed to connect knowledge of material emissions to the indoor air measurement results.
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