Presents results of a survey of natural infiltration rates in 2 identical modern homes-one gas fuelled and one electric-over aperiod of a year. Infiltration rates were determined by releasing tracer gas, usually ethane, into the main return duct and measuring concentration every half hour. Discusses results and dependence of infiltration rates on wind speed and direction. Gives preliminary result that wind probably exerts agreater effect on infiltration than any other variable.
Describes a probe, developed for sensing static pressure in two-dimensional air flow. It was designed as a sensor for the measurement of static pressure acting on the surface of a building but the design also permits it to be used in free-stream flow. Gives details of the construction of the probe, calibration procedure and the effects of Reynolds number and of the sensitivity of the probe to pitch.
Reports measurements of air pollutants inside and outside three pairs of structures for different seasons of the year. Four pollutants were measured, suspended particulate, soiling particulate, carbon monoxide and sulphur dioxide. Describes instrumentation and gives results. Concludes that in homes withgas heating and cooking, the heating system has no effect on CO levels but gas stoves had a significant effect.
Describes tests made to find wind pressure on models in a low-velocity wind tunnel. Three basic forms:- a semi-cylinder, a rectangular vertical wall and a block-type gabled building were tested at several different angles to the wind. Gives typical pressure patterns for block-type model. Suggests use of average pressure coefficient for calculation of wind loads determined from pressure distribution. A short series of tests on the effect of shielding building showed that negative pressure on some walls could be increased by an adjacent building.
Describes test rig used to measure air leakage through a metal framed window. Gives average of results of leakage for different air pressure. Finds leakage rate of 20 cu. ft/h/ft for air velocity of 30 m.p.h. which was generally less than published results.
Reports measurements of ventilation rates made in a nine-story office building. Two methods were used; tracer gas decay rate using sulphur hexafluoride and a direct method when air flow rates through roof vents and exhaust units were measured. Gives summary of results and finds good agreement between the two methods.
Provides table showing that annual heat loss through windows in U.S. accounts for about 5% of total energy consumption, or around 1.5 times energy derived from oil transported by alaskan pipeline, costing $30 billion annually. Describes relatively simple window treatment to eliminate substantial portion of thisloss which involves tightly sealed, interior-applied insulating panels. Demonstrates how performance of several such systems was predicted and verified by standard test methods.
Detailed sets of time-averaged surface pressure coefficients were recorded over the walls and roof of a rectangular building model, set in a simulated high density urban area. The 1/400 scale model represented a generalized smooth surfaced building of 100x150 ft plan form, whose height varied from 300 ft to 200,100 and 50ft. Surrounding roughness elements equalled the heightof the 50ft, building model. Tests were carried out at twelve wind angles using a power low velocity profile with an exponent of 0.43.
Describes methods of measuring the air tightness of whole buildings. Outlines three tracer gas methods; constant concentration; decreasing concentration and constant emission. Describes pressurisation method. Describes measuring equipment and test procedure and discusses calculation of ventilation rateand error magnitudes. Gives brief summary of measured results and an appendix contains a print-out of data on the airtightness of houses.
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