English

This paper presents and evaluates a new method, based upon tracer gas techniques, for determining interzonal airflows and effective volumes in a multizone enclosure. Presently used tracer gas techniques have a number of drawbacks including the need for multiple tracers when analyzing a multizone structure. Also, traditional techniques cannot be used to independently determine flows and volumes in the multizone case. The method described in this paper eliminates some of the problems introduced by multiple tracers and allows the independent determination of both flows and volumes.

Moisture and mould in buildings have become fairly common problems in Italy, particularly since regulations aimed at energy conservation have been enforced in the seventies. Results of a case study conducted within IEA Annex XIV are presented in this paper. Two flats belonging to the same building (one with and the other without moisture problems) have been monitored during the winter 1987-88. Indoor temperature and air humidity, wall surface temperature and weather parameters were recorded for several weeks using two automatic data loggers.

It is particularly important to be aware of the air flow pattern in a building when determining indoor air quality problems or calculating space conditioning loads for energy consumption. Correct sizing of space conditioning equipment is also dependent upon accurate air flow information. A number of infiltration models have been developed to calculate infiltration-related energy losses and the resulting air flow distribution in both single-zone and multizone buildings.

The air flow within a room, the interchange of air between rooms and the interchange of air between a building and the exterior are topics which until today have received little attention by researchers.

This paper deals with the elaboration and the validation of a userfriendly numerical program (EOL) for the calculation of the ventilation patterns inside industrial premises. After the running-in. In period, "EOL" will be used by the technical staff in charge of ventilation projects. Here is set out the EOL unit devoted to the calculation of the mean flow inside the rooms. The structure of the software (presently restricted to two-dimensional mean flow configurations) is explained.

Whole-building pressurisation tests can quantify the air-leakiness of a building's external envelope. The resulting information can be used in assessing the quality of the building fabric. At present there is little information regarding the leakage characteristics of large, non-domestic UK buldings. As a step towards providing more information, the Building Research Establishment (BRE) has developed and constructed a multifan pressurisation system known as BREFAN to pressurise large buildings like offices and hangars.

In the "Stockholm Project", different blocks of multifamily buildings have been extensively monitored for about three years. Temperatures, airflows and electricity use have been registrated each hour. As an additional base to this examination, ten fan units in the buildings have been intensively studied. The results show that the specific use of power for transportation of ventilati n air varies between approximately 1 and 4 kW per m³ and second. The results from the measurements indicate a notably low level of installation efficiency.

A test room with a Displacement Ventilation System has been built. Air velocity and temperature profiles were measured at different places in the room under summer and winter conditions. Additional numerical simulations for the same conditions as in the experiment were performed. The measured and calculated values showed good correspondence. An office room is normally not occupied permanently therefore its transient ---behaviour was also investigated.

This paper describes the development of a microprocessor-controlled tracer gas system which is capable of collecting a large number of tracer gas samples at short or long intervals. The system can be used for accurate measurement of air flow through openings, e.g. cracks, windows and doorways.

A demand controlled air ductwork should be so dimensioned that the flow controllers have good flow and acoustical operation conditions. From the air flows in a room and its highest permissible sound level, the highest differential pressures allowable to the air flow controllers (duct air flow controllers and terminal devices) are selected.