This paper describes the new indoor environment research facility recently constructed at the Institute for Research in Construction, National Research Council Canada. This facility allows full-scale testing and physical modelling of office space lighting, thermal comfort, indoor air quality, airflow and contaminant-flow patterns, ventilation, acoustical characteristics, and occupants' reactions to these parameters. The facility consists of a test room, approximately, 12 m by 7 m by 2.74 m high, with adjustable interior partitions.
The Dutch E novation program is a national demonstration program in which dwellings with high energy consumption, moisture and mould problems and poor indoor air quality were renovated, with special attention to the selection of the heating and ventilation systems, thermal insulation and the building physical details. A number of indoor air quality parameters were monitored before and after renovation, showing an important improvement in the indoor air quality.
Three different examples illustrate the possibilities offered by the use of tracer gas methods for detailed airborne moisture transport studies in building. The first one concerns an individual dwelling with severe condensation problems, the second one gives an example of statistical data collection of humidity related parameters in 18 apartments and the last one focuses on the evaluation of the amount of water evaporating from the building materials of a recently built low energy dwelling and on the energy consumption required for drying the construction.
In order that sampling points may be strategically located, it is desirable to have knowledge of the spatial variation of ventilation eflectiveness parameters prior to measuring them using tracer gas sampling techniques. The research described in this paper is being carried out to establish a tracer gas sampling strategy as well as to facilitate the prediction of ventilation effectiveness parameters. The procedure developed requires the division of the internal space into a large number of cells and, by the application of CFD, the mass flow rates between adjacent cells to be established.
Thirty-one independent fan pressurization measurement series were performed on seven apartments in three family housing buildings at Fort Riley, Kansas, using four protocols. The tests followed procedures in new or revised fan pressurization standards by the International Standards Organization (ISO), American Society for Testing and Materials (ASTM) and Canadian General Standards Board (CGSB). In addition, the effect of interzonal flow was considered. The three standards gave similar results.
ASHRAE has developed a draft of a measurement standard, Standard 129, entitled "Standard Method of Measuring Air Cliange Effectiveness." This standard defines a method of measurement for measuring air change effectiveness in mechanically ventilated spaces, and provides a discussion of how the values of air change effectiveness may be used to demonstrate compliance with ASHRAE 62-1 989.
This paper describes a method which aims to generate an overall view of multizone building air flow by integrating methods for bulk air flow analysis, air flow field analysis, and building thermal analysis. This has been achieved by implementing a computational fluid dynamics approach within the ESP-r building energy simulation environment which already incorporated a model air flow network approach. The current state of the method is demonstrated by a case study. The main conclusion from this is that the integrated method is very promising.
In line maintenance hangars, air planes stay about 2 hours, usually at night-time. The coolingdown of the inside air during the opening time of the hangar gates (up to 5 times per night, lasting 15 to 30 minutes each) has a considerable impact on the comfort conditions for the workers, and on the energy required for reheating. The time-dependent air flow rates and associated heat loss rates during the door opening and closing cycles is assessed by simple transient thermal models and CFD (Computational Fluid Dynamics) calculations.
Office workers continue to complain about air quality problems, and a significant industry has developed to measure pollutants and environmental conditions such as temperatures and humidity. The effectiveness of the ventilation system is often ignored because it is a difficult measurement to carry out and interpret. The results contained in this paper make a start towards understanding the performance of mechanical ventilation in New Zealand office buildings.
The workplaces located in southern (18 places) and central Finland. The total amount of workrooms measured was 87. The mean concentration of radon was 254 Bq/m3 (range from 12 to 1647 Bq/m3) during working hours. The calculated radon entry rates varied from 2 to 4780 kBq/h. The measured air exchange rates varied from 0.1 to 13.3 l/h and calculated ventilation flow rates varied from 30 to 55200 m3/h. Radon concentration was found to depend on the type of foundation, whereas types of ventilation or the ventilation flow rates did not correlate significantly with the concentrations of radon.