States that the reduction in energy losses due to reduced air infiltration is often overestimated because the effect of open windows is not taken into account.< Shows that the habits of airing are rather similar in some European countries. The proportion of windows open or ajar is inversely proportional to the indoor- outdoor air temeperature difference over a large interval of this temperature difference.< The proportionality constant seems to take a value that is independent of the building construction or the heating system of the residential building.
Measures air infiltration and tightness of Swedish houses using the tracer gas technique and the fan pressurisation technique. Uses a previously developed model correlating air tightness and infiltration to evaluate the performance of Swedish homes. Shows that it is difficult to achieve the recommended minimum ventilation rate according to the Swedish Building Code by relying on natural air infiltration. Most new homes do, however meet the Code's stringent air tightness requirements. A comparison with American houses show that Swedish homes are very tight.
Presents the latest results of air infiltration research in Finland. The aim is to increase the knowledge of the influences of air infiltration on energy consumption, ventilation and indoor climate. Briefly describes the principles of a calculation model for predicting the interconnection between airtightness and air change rate. Describes improvement of air tightness in Finnish buildings, with special attention to construction details. Discusses possibilities of draughtless and controlled fresh air intake through the building envelope.
Reports on a comparative study of residential infiltration as predicted by computer model and as measured in the Mobile Infiltration Test Unit (MITU) as well as in selected test houses, both occupied and unoccupied. Sensitivity analyses were also conducted on each parameter contained in the model against data obtained from MITU.
Describes a technique developed for measuring air flows between internal spaces of houses. Involves using a portable gas chromatograph to monitor the concentrations of three tracer gases released in three distinct zones within the building envelope. Using the results of each measurement, which takes approximately two hours, the ventilation rate of each zone can be calculated along with the interconnecting air flow. Presents the tracer gas equations involved, and includes an account of the experimental method and the practical difficulties encountered.
Discusses the use of a regenerative, air-to-air, rotary heat exchanger as part of a controlled ventilation system in a modern tightly built house. Describes analytical studies and the construction of a prototype. A four-month trial ina test-house indicated that the unit would be capable of recovering 5000 Kw/hof waste energy if operations were extended over the full heating system.
Gives measurements of the ventilation as well as the temperature efficiency of mechanical supply and exhaust systems (balanced systems). The ventilation efficiency is a measure of the performance of providing air in the occupied zone and is also an indicator of the air quality. The temperature efficiency is a measure of the system's capability of supplying heat in the occupied zone. Monitors ventilation efficiencies by adopting tracer decay techniques and the temperature efficiencies by measuring the stationary temperatures.
Reports measurements on air transport through homes made by a committee working a Dutch Standard on Heating Load Calculation similar to DIN 4701, but taking account of air infiltration losses through joints and cracks between glazing, window-frame and facade construction. Describes the measuring method applied. Tables air leakage coefficients c and flow exponents, n ,of a number of flats and single family houses. Also tables c and n values of cracks according to type of construction and material, use of weather strips and measuring institute.
Describes methods of measuring the three-dimensional flow field using a three-sensor hot-wire probe, with emphasis on the techniques developed by the author's group at the Pennsylvania State University. The hot-wire equations, data processing procedure, calibration techniques, and a discussion of various errors in the measurement are included. Some typical data acquired by thisprobe is also included.
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