Investigates the efficiency of models describing infiltration and natural ventilation in buildings. Considers 8 different models. The parameters of the models are determined by fit to data from 6 different ventilation experiments in residential buildings. The number of parameters in each model is varied and the effect of this on the model efficiency is evaluated. The effect of simple corrections of the models for a dependence on the wind direction is considered.
Describes a field study carried out to evaluate the effectiveness of the air leakage sealing techniques employed by Ener-Corp Management Ltd. for reducing air infiltration in houses. Performs presealing and postsealing air leakage tests on 82 single detached houses, located in Winnipeg or southern Manitoba. The sample group consisted of 56 conventionally-constructed houses of varying size, style, occupancy and airtightness, and 26 nonstandard structures of smaller but identical size and age. This latter group was part of the Flora Place Project.
Discusses the extension of an infiltration predicting technique to the prediction of inter-room air movements. Air flow through openings is computed from the ASHRAE crack method together with a mass balance in each room. Verifies technique by comparison to published experimental results. Results indicate that the simple model provides reasonable results for complex 2 way flows through openings. The model is as accurate as the available data, about+-20%.
Studies the techniques and issues related to evaluating the airtightness of homes. The first section discusses the physics of air infiltration and the techniques used to measure infiltration rates. Also discusses pressurization testing and its relation to infiltration. The second section presents experimental work aimed at several questions raised in the first section. A long term experiment involving weekly pressurization testing of a home reveal the short-term reproducibility of the test results and the seasonal variation in a home's tightness.
States that in a tight house with a vapour barrier, an air management system is needed to provide fresh air and remove the build-up of moisture generated by the occupants. Briefly describes a typical air management system,incorporating an air-to-air heat exchanger, and discusses the need to provide an acceptable ventilation rate, which controls pollutant level but minimizes heat losses.
Describes some new theoretical and experimental techniques developed by British Gas to investigate the ventilation of buildings. These include:< 1. The multi-cell model "vent" for predicting ventilation rates< 2. "Autovent", the multi-cell constant concentration tracer gas technique used for measuring ventilation patterns in buildings.< 3. Pressurization techniques for measuring air leakage in buildings.< Gives a selection of results from applications of these techniques to show their scope.
Studies the ventilation of 9 air-conditioned animal rooms used for both housing and experiments. Samples dust, measures ventilation rate by anemometers and by tracer gas decay, and uses settle plates to determine the number of airborne bacteria. Detects a high amount of pariculate matter emanating from the animals which might sensitize personnel working in these rooms. Previously, attention has been paid to the ventilation requirements of the animals but where people also spend several hours in animal rooms then safety conditions for staff must be considered.
Measures the air change rate in 2 atrium houses and in 6 terrace houses. Examines the possibility of allocating the air change to particular rooms by correctly placed and operated exhaust ventilation and ventilation openings. Concludes that in dwellings with mechanical exhaust the fresh air change rate only depends slightly on the ventilation openings being opened or closed, and that it is possible to direct fresh air flow into different rooms if the doors within the house are not tight.
Writes for experts and non-experts on calculation methods for energy consumption in buildings. Gives a brief introduction to the physical and numerical bases used in this field. Presents the calculation methods investigated, selected to cover the simplest as well as the most complex methods in use. Describes calculation examples used for prediction of energy consumption and conservation. Analyses the calculation results and gives conclusions and recommendations. Concludes by covering work carried out on the influence of the inhabitants.
Presents a model for computing the infiltration and air flow between rooms of a multi-room building in terms of basic principles of fluid mechanics. Incorporates model into a comprehensive loads-predicting computer program, and calculates air flows, room temperatures and heating loads for a typical townhouse. When the inter-room openings of a low-rise structure are large compared to the envelope openings, the infiltration and total load can be accurately and more quickly computed by assuming no resistance to air flow between rooms.