The characteristics of the climate in Taiwan are high temperature and humidity. In order to solvethese basic problems in dwellings, a meteorological station was established in Fulong(northeastern part of Taiwan) to document the detailed microclimatic information of indoor andambient environments during 4 years. According to the hydrodynamics and thermal mechanics,the new ventilation strategy was developed with the thermal mass cooling-down systemconstructed as the porous floor in a full-scale climate chamber.
The air-conditioned office building design in the tropical hot-and-humid climates has seldomtaken into account adaptation principle to thermal comfort. This induces the occupants to findcomfort at the pre-determined comfort criterion in air-conditioned enclosure and they soondevelop a higher expectation of homogeneity that in turn leads to demand of coolertemperatures. Though the research knowledge is large, practical implementation has aptlyignored the variability of individuals comfort criteria.
This paper presents the performance of a displacement ventilation system in a thermalchamber with tropical subjects. The chamber is served by an Air-Conditioning andMechanical Ventilation (ACMV) system in either Mixing or Displacement Ventilation modes.In the experiments, tropical subjects were surveyed with respect to their thermal sensationsunder different room conditions in either displacement ventilation or mixing ventilation.Objective measurements such as room air temperature, air velocity and relative humidity weremeasured at different heights in the chamber.
This paper shall investigate thermal comfort requirements for university students in the hot-humid region of Bahrain and the hot-dry region of Saudi Arabia. An extensive field survey shall be conducted among university students in an attempt to define optimum comfort requirements. The field surveys shall deal with the following aspects:
Recording climatic variables, which influence thermal sensation, these are; ambient temperature, radiant temperature, relative humidity and air velocity.
Present international standard for thermal comfort such as ASHRAE Standard 55 and ISO 7730 were developed to serve as a guideline for moderate thermal environments e.g. mechanically airconditioned spaces [CEN ISO 1995]. Recent thermal comfort studies had reported that some discrepancies were observed in its application for Naturally Ventilated (NV) buildings in hot and
Thermal comfort variables were measured in Singapore mechanically ventilated classrooms. In parallel the cccupants filled questionnaires on their perception of the indoor climate. The results showed that ASHRAE Standard 55 was not applicable in free-running buildings in the tropics. The study showed that generally cool thermal sensations were more readily accepted by the classroom occupants than warm thermal sensations.
This paper is a report on humidity control in schools mainly located in hot and humid climates : according to the US Department of Energy's investigation, most of them, use packaged cooling equipments that are not able to manage space humidity effectively when delivering a high percentage of outdoor air. Those schools don't respect the requirements of the ANSI/ASHRAE standard 62-1999.
By using the dedicated outdoor system (DOAS) approach, ventilation effectiveness and humidity control can be improved and meet the recommendations of the ASHRAE 62-1999 standard.
The construction of dwellings for people with low incomes in developing countries encompasses a broad range of issues starting from the choice of the building site, to the construction phase and finally to the evaluation of the building itself. For tropical climates, the thermal evaluation of low-cost dwellings should be primarily related to the optimization of internal comfort conditions. Usually low-cost housing projects are implemented throughout Brazil equally, with no concern to the climatic region where houses are to be built.
The paper compares a long and short term study of naturally ventilated buildings in a city in western Iran. For the hot season the neutral temperatures from the short and long term studies were 28.4 and 26.7 deg. C. For the cold season the short and long term neutral temperatures were 20.8 and 21.2 deg. C. Good agreement is shown between both studies. The results showed how acceptable conditions varied widely, a good relationship between neutral temperature and room temperature and between indoor comfort and outdoor conditions.
Proposes an HVAC system which combines chilled ceiling with desiccant cooling, to be used in hot and humid climates where air dehumidification is necessary in order to maintain the indoor air humidity within a comfort zone and to lessen the risk of condensation on chilled panels. The system decouples temperature and humidity control by using desiccant wheel for moisture removal and ceiling panels to control the temperature. Another three systems were viewed to evaluate the system performance and energy savings potential.
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