Describes an investigation to see what energy saving can be achieved by the regulation of mechanical ventilation systems in high rise buildings. Measures air leakage in a block of flats, and uses a calculation model to predict the amount of energy lost due to ventilation in various situations. Concludes that the reduction of ventilation has no disadvantageous consequences for the operation of the system, and that the extracted air flow is affected more by incorrect adjustment of extractor vents then by opening windows, regardless of the setting of the ventilator.
Describes results from wind-tunnel tests on models of the Building Research Establishment's experimental building at Aylesbury. The use of several scale models of this building in uniform and in simulated atmospheric boundary-layer flows together with the results from the full-scale experiments allow an assessment of the effect of variations in the ratio of the longitudinal- turbulence integral length scale to body dimension.
Describes the relationship between wind flow round a building and heat loss from it. The relative merits of numerical and wind tunnel models are discussed and various numerical techniques, including the vortex method and the control volume method, are examined.
States that one of the major difficulties in estimating air infiltration rates in buildings is lack of full scale data on pressure distribution on various structural shapes located in different types of surface roughness category. Tries to fill this gap by studying two building structures of different shapes and situated in different environments, registering the mean pressure distribution and calculating the rate of air leakage due to openings. The first house is of old type construction and in a `semi-urban' environment.
Describes the results obtained and the problems encountered in the sealing and testing of 15 homes in Ottawa Ontario, for the Ontarion Ministry of Municipal Affairs and Housing. Gives a data summary for the 15 homes, outlining house characteristics, reductions in air leakage, materials and time needed. Finds that the average air leakage reduction is 38.7%, and the average time taken to perform the sealing and testing is 31 hrs. Covers:
Uses a similitude approach to develop predictive graphs for the ventilation rate due to the stack or chimney effect. Uses a half scale model of an open side wall structure with a continuous and restricted open ridge, and finds that:< 1. Ventilation rate is approximately proportional to ridge outlet width< 2. Outlet Reynolds number response ie ventilation rate to changes in Grashof number is a function of the ratio between building height and ridge width.
Looks at the requirements for computer model validation, especially in regard to predicting energy usage in buildings. Discusses the IEA project for comparing and validating several computer programs in this context. Describes the Glasgow commercial building monitoring project, which includes detailed measurement of temperature and air flow rates to provide data for model validation. States what type of data is needed for validation.
Lists three factors causing a high radon and radon daughter concentration in Swedish dwellings:< 1. By energy-saving measures the ventilation rate has become low.< 2. 10% of existing houses are built of light-weight concrete with a high proportion of radium.< 3. Large regions have high radium content in the ground.< Describes a method for detecting high radon daughter levels by measuring gamma radiation from the outside.
Shows that recent investigation has revealed harmful pollutants in greater concentrations in energy-conserving buildings then in the surrounding outdoor air. Some of the pollutants found include particulate matter, carbon monoxide, formaldehyde, nitrogen dioxide and radioactive radon. In the use of some construction materials, measures intended to reduce energy consumption may contribute to the buildup of indoor air pollution. Reviews characteristics of indoor pollutants and major methods of control.
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