English

The Dutch organization for applied scientific research TNO in Delft developed asystem of Controlled Natural Ventilation (CNV). It is produced by the Dutchventilation fm Brake1 in Uden.

Airtightness measurements are not yet common in the Italian dwelling stock. In the frameworkof the MICA-ENEA contract, three dwellings were chosen to study the energy performanceon the influence of natural agents. The majority of the dwellings in Italy still nowdays rely onnatural ventilation and records of the fluidynamic and energy performance are not contractualdocuments among the parties involved.

When designing a new, or retrofitting an existing building it is desirable to minimise theheatinglcooling load, total energy use and emissions from combustion. Solutions toaccomplish this has to be held up against investment costs, maintenance costs,longevity and of course indoor climate (among other things). Optimisation betweenthese different and often competing criteria is complex, and involves a lot ofparameters.

The trend towards improving building air-tightness to save energy has increased theincidence of poor indoor air quality and associated problems, such as condensation onwindows, mould, rot and fungus on window frames. Mechanical ventilation 1 heat recoverysystems combined with heat pumps offer a means of significantly improving indoor airquality as well as providing heating and cooling required in buildings.This paper is concerned with the development of a novel ventilation I heat recovery systemfor the domestic market1.

Includes sections on modelling and control algorithms, equipment and envelope characteristics, ventilation performance and building airtightness, ventilation strategies and pollutant transport, NATVENT - overcoming technical barriers, and cooling and indoor air quality in commercial and public buildings.

This paper presents a set of detailed experimental data of room airflow with displacement ventilation. These data were obtained from a new environmental test facility at the Massachusetts Institute of Technology (MIT). The measurements were conducted for three typical room configurations: a small office, a large office with partition, and a classroom. The experiment measured the distributions of air velocity, air velocity fluctuation, and air temperature by omnidirectional hot-sphere anemometers and contaminant concentrations by tracer gas at 54 points in the room.

Until now, there is no widely accepted way to express any index for this purpose and taking into account the large variety of possible pollutants. Things can be simplified if the aim is to compare different systems and strategies rather than to give an absolute value of quality. For the study of a pollutant source, the main important point for comparison is the pattern of its production, whatever this pollutant is. The detailed data for each inhabitant is the curve of the number of hours above a pollutant level concentration Ci: Nh (Ci).