In the field of ventilation engineering the understanding of jet types of flow is well established. However, the behaviour of buoyant flows with high initial Archimedes numbers has been much less explored. The aim of this short note is to highlight some of the differences between ordinary jet flow and the discharge from low velocity air terminals. Results are presented both from tests carried out in a full scale mock up and from model tests with water as operating fluid.

Air Infiltration in Norwegian buildings has been an unknown parameter. This paper is based on results from measurements in nine different buildings in Norway. 

IEA Annex 23 has been established in order to attempt to resolve these difficulties in relation to multizone air flow modelling. These models are used to evaluate the air flow between individual rooms or zones as well as the rate of inflow andoutflow of air from buildings. This approach is especially important for evaluating the adequacy of ventilation, predicting pollutant transport and evaluating airborne heat transfer between zones. Such models therefore have vital applications in both energy and air quality related analysis.

In this note we discuss the problem (concealed by the latter statement) of calculating the inside air temperature which varies with time and is, when not measured directly, in general not known. The inside air temperature (Tin), which is in betwe

In buildings with mechanical ventilation there are spaces with substantial pressure differences, which bring exfiltration, infiltration and transferred air between the rooms. For such buildings we have converted a multiple cell theory to a quadratic programming problem, and developed a computer programme, MCSPID for airflow identification. Today MCSPID is inpractical use to simultaneously determine flow rates for airsupply, exhaust air, transferred air, infiltration and exfiltration with a single tracer gas.

Although there are many simple infiltration models already available none of them have an appropriate method of dealing with what is often the single largest leak in a building; a furnace or fireplace flue. Flues are different from the distributed leakage used in simple in­ filtration models. Flues represent 10% to 30% of the total building leakage all of which is concentrated at one location above the ceiling height.