Transient modelling of convective movements in a dwelling cell

Numerical modelling of convective air movements inside a heated room was built, using a coupling of a zonal model and integral analysis. The model describes the heat transfer between air and walls, between different air layers inside the room, between air in the room and cold air jet from ventilation air supply, and between air and heat emitter. Experiments were conducted in a testing chamber with floor heating or heating by a hot water radiator, with steps in hot water and ventilation flow rates. Validation results are satisfying.

An analysis of some subjective assessments for inddor air quality in five european countries

The study in 5 European countries has shown that indoor air quality was noted depending on the country first and on the perceived thermal comfort. Moderate humidity is perceived better while temperature in comfort zone less influence indoor air quality. When it is too hot or too humid, indoor air quality is badly perceived. CO2 levels have few relationship with perceived indoor air quality.

Ventilation, energy, and indoor air quality

This paper presents a complete overview of energy and indoor air quality issues related to ventilation. It comments ventilation in standards and in practice and gives information on the human response, health effects, air distribution, ventilation efficiency and different types of ventilation systems.

Building design for good indoor air quality

This paper discusses architectural design of buildings for a good indoor air quality, material selection, building design process, relationships between indoor and outdoor air quality. It shows that the roles of architects and engineers are complementary to obtain a good indoor air quality.

Experimental study of facial air supply method for the reduction of pollutant exposure

A thermal manikin with a simulated lung was placed in an air-conditioned office with fresh air supplied in close proximity to the facial area at flow rates from 0.1 to 2 l/s. CO2 concentration measurements allow to define the fresh air utilization efficiency and the pollutant exposuer reduction efficiency.

Long term evaluation of the general thermal comfort conditions

Performance on a long-term period of time of an HVAC installation to ensure thermal comfort conditions can be evaluated by estimating the number of hours when the thermal condiitons are outside a given range. Another method consists in weighing this number of hours according to the indoor temperatures. These methods are demonstrated and discussed using data from measurements in an existing building.

Measurements and prediction of inhaled air quality with personalized ventilation

This paper examines the performance of five different air terminal devices for personalized ventilation in relation to the quality of air inhaled by a breathing thermal manikin in a climate chamber. The personalized air was supplied either isothermally or non-isothermally (6 C cooler than the room air) at flow rates ranging from less that 5 l/s up to 23 /s. The air quality assessment was based on temperature measurements of the inhaled air and on the portion of the personalized air inhaled. The percentage of dissatisfied with the air quality was predicted.

The effects of a personalized ventilation system on perceived air quality and SBS symptoms

Experiments with 30 human subjects were performed in an office equipped with personalized ventilation systems (individual control of flowrate and direction) for 6 workers and with different supply air temperatures to analyse perceived air quality and sick building symptoms.

Measurement of the airflow and temperature fields around live subjects and the evaluation of human heat loss

A special garment was developed to measure heat transfer coefficients (convective and radiative) of the clothed human body. It was tested on male subjects operating seated office work in a environmental room. The measured convective and radiative heat transfer coefficients are in good agreement with the PMV model and a number of previous publications.

The impact of humidity on health and comfort in an office building

Monitoring of temperature and relative humidity was carried out in an air-conditioned office building during the heating season. In addition, occupants filled in health and comfort questionnaire. Without informing the occupants, humidity was reduced in an experimental area compared to the control area. As this reduction was not so great (2% relative humidity), the differences of occupants perception between areas are not significant. A slight reduction of building related symptoms was observed at higher humidity.

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