humidity

Material properties, water vapor permeability, sorption/suction isotherm and moisture diffusivity, are prerequisite for application of all hygrothermal models. Based on the experimental results and well-determined material properties, a numerical model was validated. This model was then used to analyze the sensitivities of the moisture flow across imperfect hydraulic contact interface with respect to these three material properties.

The main goal of the present study was to determine thermal comfort parameters for dwellers of low-cost houses for a given set of indoor environmental conditions. 112 people living in over 60 dwellings were interviewed, according to a comfort questionnaire where information regarding age, sex, clothing, level of activity, thermal sensation and preference of the subjects was collected. Environmental factors such as air temperature and humidity were simultaneously registered with T/RH data-loggers. Results were then analyzed by comparing subjective and environmental factors.

In the present communication, a psychometric model has been presented to evaluate the performance of rotary desiccant wheels based on different kind of desiccants e.g. silica gel and LiCl. The developed psychometric model is based on simple correlations between the relative humidity and enthalpy of supply and regeneration air streams. The model is used to predict the performance of three type of desiccant rotors (Type-I, II and III). The model is tested corresponding to a wide range of measurement data.

Indoor air quality differences were investigated among five schools with and five schools without active humidity control systems. The active humidity systems provided approximately 15 cfm/person of ventilation air, while the schools without the active humidity control systems averaged less than five cfm/person. The space humidity levels in varying widely without active humidity control, and rose to unacceptable levels during summer shut-down periods.

Few studies dealing with the effect of displacement ventilation on humidity gradient in a hot and humid region have been made . In this paper it is done with a case-study approach (measurements were made in a factory located in the Tropics). The results indicate that the humidity gradient is as significant as the temperature gradient..

Discusses how the design of modern swimming pool leisure complexes must adapt to the diverse demands of today's users. States that the air treatment in a covered swimming pool complex depends on a fragile balance between the demands of occupant comfort and the technical imperatives for the conservation of the building structure. It is also of utmost importance to pay particular attention to precisely quantifying the thermal needs, defining the air flow and thermal means of operation, and selecting a principle for dehumidification which is well-tuned to its application.

States that quite simple formulae can be used for humid air, but that this is not the case for humid temperature. Gives an overview of the iterative method to be used in this case.

Describes a global approach to passive design of naturally ventilated buildings situated in the French overseas territories. This approach involves all those involved in the buildings creation process, including architect, owner, building physicists and climate engineers. A validated thermal and airflow building simulation software was used to assess the design and sizing. A reference document was created from the optimal technical specifications, and has been used to build over 800 new pilot homes.

There are important benefits to come from using passive techniques as opposed to artificial cooling. They may not be sufficient to provide thermal comfort throughout the year in wet tropical areas, however. Few experiments have been performed on the thermal performance of buildings using a mixed-running strategy in warm-humid climates. The paper attempts to demonstrate that a possible dual-mode integrated operation can be used for such locations.

The study aimed to identify the behaviour of wind in the type of urban blocks usually found in cities in tropical climates. The results presented here were obtained in colonial type areas. The authors' approach was to establish a relationship between the clusters of buildings and the evidence of overpressures or low-pressure in proximity to the openings of occupied spaces. A prominent physical feature of natural ventilation is the maximal difference of pressure between windward and leeward building facades.