Describes measurements made in a real factory building and comparisons with the scale model tests presented in the previous report. The ventilation system of the factory building is a mechanical one with the necessary rate of ventilation designed to be less than that calculated by the conventional method. The parameters studied included air velocities measured with hotwire anemometers at the inlet openings and the temperatures in the work hall itself measured from a crane.
To develop effective monitoring and control programs for indoor radon it is important to understand the causes of the broad range of concentrations that have been observed. Measurements of indoor radon concentration and air-exchange rate in dwellings in several countries indicate that this variability arises largely from differences among structures in the rate of radon entry.
Compares in tables international requirements for housing regarding ventilation requirements of the entire dwelling, plus kitchen, bathrooms and W.C.s, living rooms and bedrooms. Discusses them. Examines the efficiency of ventilation openings and the requirements made on them. Discusses air flow through a house and the effect of wind forces. Notes how effective pressure difference is affected by the distribution of joints and air leaks.
Describes a novel modification of stroboscopic illumination used to give an unambiguous record of the direction of the flow in an otherwise conventional visualisation of a complex three dimensional air flow. The flow was seeded with small soap bubbles which were viewed by scattered light. Each flash of light was split into two periods of unequal length, separated by a short extinction, thereby marking the direction of flow on the photographs. The technique allows a more complete determination of the velocity field than can be obtained by the usual stroboscopic method.
The quantity of air in several rooms lying in a stack connected by means of fresh air and exhaust air ducts is considered as a simple model of amultistorey building. Negative pressures set up within the rooms can be equalised by adjusting the
Spatio-temporal measurements of a fluctuating pressure field acting on the side faces of a square prism of finite height in boundary-layer flows are presented for a zero degree angle of attack. Two typical neutral atmospheric flow conditions
Presents methods for the measurement of air flow rates, including methods for measuring flow in ducts, at exhaust and supply air devices and for air change rates for using tracer gas.
Describes a simple device which pressurises an enclosed volume of air adjacent to individual components in the building fabric. The air flow through the crackage is measured and the interdependence of the flow rate and pressure is examined. Windows, floors, loft traps and suspended ceilings are examined. A simple relationship is found to be applicable to individual components but no universal relationship is found for a general range of components with superficially similar cracks.
States that with double and triple glazed windows the air flow through the joints reduces the transmission heat flux. This has the effect of lowering the heat load and in particular the annual heat energy demand. The same phenomenon occurs when the windows are covered with shutters at night. Provides calculation equations.
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