Air speeds at the occupied zone were studied experimentally in seven large railway stations of space volume varying from 540- 9076 m3• The spaces are installed with mechanical ventilation systems and the air supply flow rates are from 0.455-23.67 m3 s-1• Results were analyzed by dividing the measured air speeds into different ranges. Statistical data such as the peak  value, mean value, range of the air speeds and the bandwidth are calculated. Values of the percentage of discomfort were calculated and analyzed similarly.

This paper describes a methodology based on computational and analytical modelling techniques in the prediction of building internal pressure gain functions. It first involves computational modelling of the transient response following a sudden opening, which predicts both the Helmholtz frequency and the damping characteristics fairly accurately. The parameter derived by fitting the analytical model to the computed response are then used in the prediction of the gain function.

Conjunction of Multizone Infiltration Specialists (COMIS) is a model that can be used to simulate air flow and pollutant patterns in a multizone structure. Experimental data from air flow measurements in single sided naturally ventilated spaces, common in urban environments, and from cross-ventilated spaces, are compared against predictions from COMIS. The single sided ventilation experiments were performed in a full scale building and a test cell, which led to the definition of a correction factor for COMIS.

Comfort evaluations cover air quality, thermal, visual and acoustic comfort. Today, only few computer programs allow for the integrated evaluation of several or all relevant parameters. Heat transport, ventilation as well as lighting in a room are influenced by each other. Therefore they should be integrally modelled. As a part of the IEA-ECBCS Annex 23 'Multizone Airflow Modelling', such a coupling has been realised by integrating the air flow and contaminant transport simulation code of CoMIS into the building and systems simulation code TRNSYS.

A study of the reliability of systems by considering the ability of different systems to maintain a required air flow rate over time is included in a subtask of IEA Annex 27 'Evaluation and Demonstration of Domestic Ventilation Systems'. Measurements and calculations were performed to determine the variation in ventilation rates due to variation in climate and variation in performance of the ventilation system. Dwellings with passive stack, mechanical exhaust and mechanical exhaust-supply ventilation, representative of the Swedish housing stock, were studied.

The multizone airflow simulation program COMIS was evaluated within an International Energy Agency research program. One of the steps in the evaluation procedure is to test the user-code interface, consisting not only in the appearance of the computer screen, but also in the user guide or any other tutorial or help system. The user-code interface of COMIS was then tested through round robin tests. Two types of problems were submitted to several users: a simple and well-defined problem and a real world problem. This study first allowed great improvements of the user guide.

In the IEA-ECBCS Annex 23 'Multizone Air Flow Modelling,' a sensitivity analysis procedure, that included both the Monte Carlo and Fractional Factorial analyses, was defined to evaluate COMVEN, a multizone air flow code. This procedure is here applied to evaluate COMVEN, when the simulation of the ventilation of a detached house is performed for the case of ventilation driven mainly by stack effect.