There has been lack of fact-based knowledge for design and operation of supply-air filters for general industrial ventilation. A multi-company project within the Industrial Ventilation (INVENT) technology programme was started in 1994 to tackle this problem area which is assumed to be the most problematic one, according to the feedback from end-users in several industries, who also made the initiative to this project.

The use of IR detectors to steer the ventilation is in principle an attractive approach for optimising the ventilation according to the occupants needs. In order to evaluate the performances under real conditions, one of the BBRI office buildings in Limelette (some 31 offices with in total 51 persons and a variable occupation load) was equipped with a mechanical supply ventilation system in which each terminal is controlled by an IR detector.

Mathematical models have been used by various researchers to provide both a fundamental understanding of indoor air quality dynamics and a platform for estimation of IAQ constituents in lieu of experimental measurements. Due to the diverse nature of these applications the complexity and hence applicability and accuracy of the models varies tremendously. Some models have been specifically developed for evaluation of the impact of a broad range of environmental conditions on IAQ constituents.

Recently, a lower type free-access floor system which realizes improved ease of walking and less sense of confinement has been attracting attention. However, it is known that the lower the design of the air supply chamber, the larger the non-uniformity of the diffuser air velocity profile and the greater the deterioration in room temperature distribution. In this paper, an analytical model is proposed for predicting the non-uniformity of diffuser air velocity at the design stage.

Many houses in Japan have crawl space between the lowest floor and the earth ground which is about 50 cm in height. This is considered as protection against corrosion of wood materials in the floor. Japanese building codes recommend ventilation with outdoor air in this space. In our field research, we found condensation in the crawl space in summer. This is due to low temperature of the ground and high humidity of the outdoor air which is typical of the Asian climate.

A concept of mixing ratio of piston air is developed to evaluate the portion of the injecting air from tunnel mixed with the air in platform space of metro system. And a 3- dimensional turbulent model is used to simulate the airflow in metro platform resulted by the ventilation system and moving trains. Field measurement has been conducted to verify the 3-dimensional model. This experiment is performed during the normal operation time of a metro station with constant tracer-gas injection method. The results agree well with the numerical solution.

With the growth of living standards, there is an increasing demand for the cooling of living space. Rational energy use demands the use of alternative ways of cooling because the energy consumption of compressor cooling is high. In this article a new cheap and efficient paperboard compact heat exchanger and indirect evaporative cooling are presented.