Presents diagrams showing the behaviour of air currents in two passive solar houses. Suggests some straightforward means by which repetitive patterns of discrete currents can be engineered. An appendix briefly outlines the operation of a discrete current flat plate collector with a 65 - 75% normal winter efficiency.
Presents further measurements of wind pressures on models of the experimental Aylesbury house of the Building Research Establishment (U.K.). following a previous paper in which mean pressure coefficients only were compared, this stud compares fluctuating pressures as well. In these tests, the upwind hedges of the full scale site were modelled, but found to cause little difference to the velocity profiles and to the measured pressures.
Describes exterior walls of metal studs and gypsum board, used as infill walls in frame construction of industrial, commercial and high-rise residential buildings. Discusses problems of high thermal conductivity of such walls, and the application of a vapour barrier to reduce air leakage.
Reports tests of the air leakage of 24 houses made using a fan to depressurize each house. Gives a table of results including indoor humidity, air-particulate levels, energy consumption and comfort conditions for each house. Comparison of test results with calculated values for air leakage suggests than doors and windows account for only a fraction of the total. Finds some correlation between indoor humidity, air-particulate levels and leakage.
Describes results of measurements of air leakage, surface pressures and air infiltration for several conventional and energy efficient houses located throughout the United States. The measurements are compared with predicted infiltration obtained from a simple model combining measured air leakage values and average surface pressures. It was found that within limits therewas reasonable agreement between measurements and predictions. Particular features of the energy efficient houses which reduce air leakage, and therefore air infiltration, are described.
A multitude of design strategies are available to achieve energy-efficient windows. Opportunities for improving window performance fall into six groups: site, exterior appendages, frame, glazing interior accessories, and building interior. Design strategies within these groups can improve one or more of the six energy functions of windows : solar heating, daylighting, shading, insulation, air tightness and ventilation. Gives 33 strategies for energy saving. Includes information on weatherstripping windbreaks, shutters, multiple glazing and many others.
Describes the use of mechanical ventilation coupled with heat recovery devices in residential buildings to maintain acceptable indoor air quality and conserve energy. Gives tables showing the energy saving possible with a heat exchanger.
Suggests use of an electron capture detector for the routine estimation of the SF6 content of a mixture of gases without preliminary chromatographic separation. Gives chromatogram illustrating method.
Describes Lawrence Berkeley Laboratory's air pollution research project, giving the main goals, parameters to be measured and instrumentation. Describes studies, using an experimental room of 27 cu.m., which measure the emissions from a gas stove operating under air change rates of from 0.25 to 10 changes per hour. Gives graphs of results. Finds that gas stoves generate extremely high concentrations of pollutants when the air change rate is less than one per hour.
Discusses the two methods for calculating air infiltration given in the ASHRAE handbook. These are the air change method, a gross estimate based on the number of windows and doors in each room, and the crack method based on measurements of flow through the cracks around windows and doors. Presents comparisons of tracer gas measurements with calculations by both air change and crack methods for test houses in California and Minnesota. Find agreement is adequate for sizing equipment but that the crack method underestimates infiltration at low wind velocity.
Login