Discusses the nature of stack effect, the distribution of air pressures across a building enclosure and its interior separations that stack action causes, and some of the implications of the resulting air flow patterns. Concludes that way in which stack effect is distributed across the building enclosure can be altered by design.
Examines dependence of measured infiltration rates on wind speed, indoor/ outdoor temperature difference and pressure difference. Gives results in form of graphs of measured values. Calculates air-change-rate from crack length and finds good agreement with measured air-change-rate. Suggests that this is as a result of over-estimating the effect of wind and neglecting stack effect. Finds that stack effect is more important than wind. Comparison of the two houses found that the house shielded by trees and houses had a considerably smaller infiltration rate than that on an open site.
Describes how internal heat sources such as bathrooms and kitchens can significantly influence stack effect in high rise residential buildings. Taking into account storage characteristics of surrounding walls derives relationship for determining behaviour of air temperature in internal kitchen. Discusses differences found by this method and computer method between values for ventilation heat losses according to TGL 112-0319.
The use in metropolitan cities of increasing numbers of skyscrapers in which stack effects are large and entrance traffic heavy calls for a better design of entrance for controlling both infiltration and traffic. Analyses the causes of infiltration, discusses the effect of various parameters, presents design charts for estimating heating and air conditioning loads through swinging-door and revolving-door entrances. Introduces a new design of entrance, the travelling entrance-way, and gives approximate method for calculation of air infiltration through it.
Describes computer program used to calculate the air flows and pressure differentials in a multi-storey building as a result of a combination of wind effect, stack effect and the operation of air handling systems. Describes mathematical model of building and assumptions and limitations of program. Gives complete listing of program.
Describes a general model for air infiltration which will accomodate wind pressures, stack effect and ventilation openings provided the vents are either all above or all below their respective neutral pressure levels. States that main innovation of this model is expressing the infiltration as a function of the shell leakage and of the neutral heights of each face.Describes experimental method for finding the neutral pressure level. Gives typical values of parameters for tight mid-westhouses for light and strong wind.
Reports measurements of air change rates made in the tower of an eleven-storey building using sulphur hexafluoride as a tracer gas. Inside to outside pressure differences were also monitored as a function of temperature and wind speed. Gives expression for autumn and winter air change rate as a function of windspeed. Reports finding that wind direction and stack effect had little effect on the air change rate. In this building toilet exhausts and other weather independent mechanisms were more important than natural infiltration.
Gives the results of an analytical study of the distribution of pressure differences caused by chimney action in buildings. Gives results of the way in which the pressure differences are affected by various arrangements of excess supply and exhaust air. Suggest ways of controlling stack effect, by pressurization.
Describes three test high-rise buildings and the pressure measurements made on buildings. Gives results of internal to external pressure differences against height within building both with and without the ventilation systems in operation, compared with theoretical predictions. Discusses pattern of pressure differences. Suggests feasibility of pressurizing ground floor to reduce stack effect. NOTE Futher measurements of wind on two of these three buildings are given in 'Pressure differences caused by wind on two tall buildings' Tamura G.T. Wilson. A.G. ASHRAE trans. 74 no 2 p170-181.
Reports on the air leakage characteristics of the exterior walls of eight multi-storey office buildings in Ottawa. Results of the measurements taken are given and a method for calculating infiltration rates caused by stack action has been developed andis applied to heat loss calculations using the measured wall leakage values.
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