PR1997

Existing infiltration and exfiltration calculation methods are mainly based on the stationaryapproach, where long term mean values are used for wind input data. The real wind speed is,however, varying continuously with time. Because the process of the crack flow is non-linear,using mean wind speed values will give erroneous results for the air flows.

An investigation of some Indoor Air Quality (IAQ) parameters in a significant office of the State in the area of Rome was undertaken. The aim, in future, will be to cover a wide range of situations in various buildings and organisations, to achieve data to improve the working conditions, to have a more healthy working environment, to optimize energy consumption and energy management.

The work discussed here concerns the conditions of comfort obtained in a room cooled by a fan coil in relation to the form of air flow obtained. It is based both on practical experiment and on numerical simulation using CFD code. Combining these methods allowed a large number of configurations to be studied, in association with different operating conditions for the appliance. Using the results in combination enabled a relation to be established between the problem data, the device characteristics and the comfort conditions obtained.

This study reports on the introduction of air infiltration and mechanical ventilationin a model for energy consumption estimation. The model applies to air conditionned nonresidential building and is developped to need few inputs. Existing air infiltration models arecompared and three equivalent leakage area (ELA) databases are tested on the same casestudy. Calculations of air input throught opened-doors are made to compare flows due to airinfiltration and due to natural ventilation. Simulations are made considering mean airinfiltration value and hourly values.

Many post-war residential buildings in the Netherlands have collective heating systems with poor energy efficiency. Also ventilation and DHW systems usually do not comply with current requirements. In Heerlen, the Netherlands, a demonstration was carried out in the framework of the EC-THERMIE programme in a residential building where the collective heating, DHW and ventilation systems are replaced by individual multi-functional appliances. These appliances are a recent development in the Netherlands, integrating different service functions.

This paper considers the role of passive stack chimneys in controlling indoor thermalconditions in the vernmlar houses on the volcanic island of Santorini . The quality of theenvironment within these dwellings is disputable, mainly because of the high humidity levels.A monitoring study was carried out in four actual dwellings in Santorini, two built on thesurface and two excavated into the soft volcanic rock. The temperature and relative humidztyof their main space and their chimneys were monitored and compared to the simultaneousexternal conditions.

This paper identifies the significance of pollution at five sites amongst the worst on the British mainland hence indicative of other polluted areas within Europe. Three sites are located in London and one each in Birmingham and Cardiff. The pollutants examined are NO2, SO2, O3 and PM10. Newly proposed DOE figures defining poor air quality have been used to re-examine the frequency of excess pollution episodes between 1992-1995. The results identify the most appropriate periods for natural ventilation of offices in urban areas in terms of the hour in a day and time of year.

Within the EU project NATVENT, which deals with the application of natural ventilation in office type buildings, one of the items to be studied was controlled air flow inlets. Natural air supply is a key part in the design of natural ventilation in offices. In cases these air supplies are designed in the wrong way one may expect complaints in terms of draft and stuffiness. Size and controls on inlets are vital elements in design. Controlled air inlets may help to overcome the problems of draft and stuffiness, and may contribute to an energy efficient design of the building.

An extensive experimental program on single sided natural ventilation was carried out within the frame of PASCOOL EC research project. Within the frame of these activities, four single sided natural ventilation experiments were carried out in a cell test, a full scale outdoor facility. Experimental data were used as input for numerical simulations that were carried out using air flow calculation tools based on network modeling as well as computational fluid dynamics (CFD). Finally, fuzzy logic techniques were used to predict the air velocity profile in the middle of the opening.

In the framework of the Flemish Impulse Programme on Energy Technology (VLIET), the project called SENVIVV is running from January 1995 till September 1997. The major objective is to obtain a detailed picture of various characteristics of dwellings constructed during the period 1990-1995. To achieve this, a representative sample of 200 dwellings is analysed in detail. The final report of this project is expected to be available at the end of 1997.