A simplified model of air infiltration has been developed at Lawrence Berkeley Laboratory, in order to expand the use of air flow calculation techniques outside the field of research. The validity of the programme must be checked. Benefit has been gained from work dedicated to the same problem in the field of building thermal analysis. Following this idea, a detailed validation methodology is proposed. Progression in the complexity of the modelled structures, use of high accuracy data are sine qua non to this task.
Air change rates are measured by an IR-gas-analyser coupled with a microcomputer which is programmed to control measurements as well as data acquisition and evaluation. The implemented programs provide an instant access to results. The experimental equipment is installed in compact form on mobile units. Measurements have been taken in a university laboratory by using the decay- and constant-emission-method to examine air change rates under various conditions. Typical results are presented and show where each of the two methods is more appropriate.
A computerised portable unit for measuring the ventilation efficiency by the tracer gas technique is described. The hardware of the unit is designed from readily available equipment. The software of the unit is menu-driven to be operated by computer non-experts. The software include several analytical models of ventilation processes and in the present study, age analysis and the air exchange efficiency are discussed.
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