The use in metropolitan cities of increasing numbers of skyscrapers in which stack effects are large and entrance traffic heavy calls for a better design of entrance for controlling both infiltration and traffic. Analyses the causes of infiltration, discusses the effect of various parameters, presents design charts for estimating heating and air conditioning loads through swinging-door and revolving-door entrances. Introduces a new design of entrance, the travelling entrance-way, and gives approximate method for calculation of air infiltration through it.
Describes a computer program used to calculate the air exchange in multi- storey buildings. An air network is drawn up for the building and arbitrary initial pressures are assigned. A system of equations is drawn up for all linearly independent loops andjunctions and the program solves this system of equations. States that comparison with the hydraulic analogy method gives a discrepancy, not greater than about 3%. NOTES translation available from B.S.R.I.A. price 1 pound
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.
Describes experiments aiming to estimate the protection afforded by a shelterbelt on the plains area of America. Describes three test houses and gives test results. The three houses were unprotected, partially protected and closely protected by a slat fence. Gives basic data in the form of fuel use, wind and temperature. Concludes that the reduction in wind speed by windbreaks is of the general order of 35% with a proportional saving in fuel. Finds that the area of tree shelterbelts has themost important effect on the degree of wind reduction.
Calculations of water vapour flow through walls and ceilings are frequently based on the permeability of building materials and implicitly assume that most of the vapour transport takes place by diffusion. Finds that this model is generally inval
Describes research project to find air leakage values of walls of elevator and stair shafts in order to use these values in the design of pressurization systems. Describes method of test and gives results. Concludes that leakage rates for walls of elevator shafts constructed of masonary units are higher than those of cast-in-place concrete. Variations in the leakage of stair shafts could not be related to the type of wall construction but probably depended on the workmanship in sealing crack openings.
Documents and compares the air infiltration levels experienced in five Twin Rivers townhouses before and after retrofit. The retrofits sealed and caulked window frames, sealed cracks along the attic floor/party wall Junction and reduced leakage from basement to attic. Weather data and air infiltration rates were analysed using multiple regression, polar plotting, stemleaf plotting and comparisons of infiltration rates with inside to outside temperature differences. Gives results in graphs and tables.
Describes a general model for air infiltration which will accomodate wind pressures, stack effect and ventilation openings provided the vents are either all above or all below their respective neutral pressure levels. States that main innovation of this model is expressing the infiltration as a function of the shell leakage and of the neutral heights of each face.Describes experimental method for finding the neutral pressure level. Gives typical values of parameters for tight mid-westhouses for light and strong wind.
States that porosity is the most important single parameter describing shelterbelts but is very difficult to measure or define. Describes a method for categorizing wind breaks in terms of porosity using only measured minimum leeward-wind velocity. Gives theoretical expressions for the flow through a porous shelterbelt. Describes experiment to measure wind velocities around shelterbelts of low, medium and high porosity. Shows that wind measurements could be made any height without affecting relative reduction in velocity.
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.