Reports wind tunnel investigation of the air flow around single houses and in passages between two single buildings. Wind velocity around the house was measured using thermistors and results converted to isovel maps, that is maps showing curves joining points of equal velocity. Gives diagrams showing isovels.
Describes main features of full-scale wind load tests made on Royex House, an 18-storey office block in London. Wind tunnel tests were made on a model of the building and the results compared. Concludes that wind load on building is almost entirely on the windward wall, short duration gusts are significant in loading the building. Finds reasonably close agreement between wind tunnel and full scale tests in the matter of overall drag coefficient, but an assessment of the pressure distribution on the surface of a building requires a model with permeable walls.
Describes series of wind tunnel investigations leading to development of a procedure for estimating wind pressure forces on low-rise building which is part of a large group of similar buildings. Procedure takes account of geometrical form of building, spacing of buildings, direction of wind and upstream fetch conditions. Gives estimated value as pressure coefficient which may be determined graphically.
The two-storey house at Aylesbury, England, built by the Building Research Establishment for the full-scale measurement of wind pressures has been modelled at 1:500 scale in a boundary layer wind tunnel to verify the reliability of simulation forlow-rise buildings. Describes wind tunnel tests of buildings models of 5 and 22.5 roof slope. Compares surface pressure measurements with full-scale data for various wall and roof locations. For the model terrain best modelling conditions, the results show agreement which is encouraging.
Describes wind tunnel tests on cubical models with roof angles of 0, 15, 30 and 45 and on a wall placed in constant velocity and variable velocity air stream. Discusses the effect of velocity distribution on pressure distribution and wind loads. Presents results in the form of diagrams of pressure coefficients over the models.
Reports systematic pressure distribution measurements made on models of rectangular buildings of various heights with gabled roofs of different slopes in a wind tunnel. Describes the models and test procedure. Gives results in the form of graphs of mean pressure coefficients for different roof pitch, building height and wind direction. An appendix shows how mean pressure coefficients are obtained from section pressure coefficients, giving graphs of section pressure coefficients over the ground plan of the buildings and the raised roof structure. NOTES translation available from B.S.R.I.A.
Wind tunnel test conducted on a scale model of a classroom show that, provided the test air speed is kept in excess of about 3mph, it is feasible to use models for predicting, with good accuracy, the air-flow conditions in and around full-scale buildings. In the case of low-pitch roofs the height of the stagnant zone set up as a result of flow separation occurring at the windward eaves of a building is influenced by wall height rather than by roof pitch.
Developes a simple procedure for calculating exterior wall pressure differences and air infiltration rates for various wind velocites and direction by applying the pressure data obtained from a wind tunnel model study to a computer model building. Gives separate expressions for air infiltration caused by stack action and by wind and an expression for the combined effect. Gives example of infiltration calculations compared with computer results and finds good agreement.
Reviews current status of research in North and South America relevant to the prediction of tall building behaviour in response to wind. Four main headings are considered a)meteorological research-wind structure and climate, b) full- scale investigations of wind action on tall buildings, c) development of wind tunnel techniques for building aerodynamics, d) simplified theoretical models of wind effects on tall buildings.
Describes adaptation of photo-electrical optical technique to measure ventilation rates in wind tunnel models. Illustrates probe photographically and diagrammatically. It comprises essentially a light-emitting diode and a hybrid photodiode-amplifier detector. Compares technique with conventional tracer gas technique using helium and a katharometer and finds good agreement. Considers optical probe has considerable potential for measurements in small and multi-celled models where conventional techniques are not feasible.
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