Describes a test method for determining the overall heat loss coefficient of a house. Bases method on the statistical correlation of measured heat consumption with outdoor weather data. Derives a regression equation from the heat balance giving the relation between indoor air temperature, internal heat production and the outdoor weather data. Continuously monitors the power consumption (from electrical heaters) in an unoccupied house, together with indoor air temperatures and outdoor weather data, as solar radiation, outdoor air temperature and wind velocity.
Long-term efforts in Belgian research has led to the development of computer models for energy consumption predictions. Describes some simplified methodologies to be used for quick analysis of situations, especially in 2 cases:< 1. The analysis of the impact of certain design options on the thermal and energy balance of a house.< 2.
Notes that ventilation efficiency is not referred to directly in the new DIF standards for ventilation effciency. Reasons for this are that there are no clear definitions for the term or instructions on how optimum ventilation efficiency can be achieved under different operating conditions. Describes some measurements carried out on ventilation efficiency in non-industrial premises.
Reports on conference arranged by AIC where main topic was different building standards in different countries. Discusses condensation problems in UK housing and frequency of toxic gases in Scandinavian housing. Notes research into more efficient ventilation and future expectations.
Notes that there is currently no generally accepted term for the efficiency of a system in terms of pollution removal. Different proposals have been suggested. There is now sufficient factual data to determine the difference inability of different systems to evacuate pollution. This is despite the factthat the requirement for minimum flow is the same for all fan-assisted ventilation. The requirement is also unrelated to whether the system is an extract or push-pull system and where the ventilation devices are positioned.
Describes measurements of the leakage area of fireplaces,bathroom and kitchen exhaust vents, electrical outlets and leakage in the ducts of forced air distribution systems. Makes component leakage measurements in a total of 34houses in Atlanta, Georgia, Reno Nevada and the San Francisco Bay area. Finds damperless fireplaces and ductwork to be the most significant sources of leakage in the western houses.
Measures houses with energy efficient designs in Eugene, Oregon and Rochester (NY) for effective leakage area using blower door fan pressurization. Determines air change rates by tracer gas decay analysis. Makes fan pressurization measurements on 13 new houses in the San Francisco Bay area that have been partially sealed with polymeric foam sealant. Measures a similar group of 13 unsealed houses as a control. Uses the results of thesemeasurements in conjunction with an infiltration model developed at LBL to predict average annual and heating season infiltration rates.
Describes a simple, inexpensive sampling technique for infiltration measurement using SF6 tracer gas. Uses pre-evacuated blood collecting test tubes with rubber stoppers for sampling. This is controlled by a micro-processor driven automatic sampler, which drives a hypodermic needle through the rubber stopper to fill the tube with an air sample. Analyzes samples using a gas chromatograph. Releases SF6 at ground level in a high-rise cold store and collects samples of air at different heights to see if stratification is present.
Measures air exchange across open cold store doors using an anemometer and by tracer decay methods. Anemometer results show that an empirical factor of 0.68 should be applied to the predictive equation by Tamm. Observes a further reduction in air change rate (about 47% reduction) due to imperfect mixing of the air. Air curtains reduce infiltration by about 75-80% and plastic curtains by approx. 93%. Forklift traffic and internal circulation fans also affect air change rate.
Describes a programme undertaken by the AIC to validate mathematical models of air infiltration. Uses experimental data to assess the reliability and full range of applicability of air infiltration models, and to identify key parameters that
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