At first, this paper deals with the history of indoor environment and ventilation , with the evidence that a good IAQ is essential for public health. An inadequate ventilation plays a major role on the global burden of allergies, airways infections. The more complex the HVAC system is, the more liable it is to fail (if improper maintenance) sothe non-industrial indoor environment is the most important environment from a human health perspective.
This paper deals with the CFD (Computational Fluid Dynamics) method used for the analysis of the micro-climate surrounding the human body. The airflow characteristics of inhalation and exhalation are analysed under both steady and unsteady breathing conditions. The various examples given in this report make clear that CFD is a very effective and powerful tool for analysis and design of healthy indoor environments.
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.
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.
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.
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.
Ventilation and indoor air characteristics were measured in 63 apartments for elderly people in Finland and residents were inquired about indoor climate. Results are shown and analysed.
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.
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.
A personalized ventilation system located underneath the front edge of a desk was tested regarding to its ventilation efficiency using a heated mannequin and tracer gas. The air change effectiveness ranged from 1.4 to 2.7.