wind

This report describes a technique which models the infiltration process for an entire enclosure more accurately than standard methods. Both air flow and convective/conductive heat transfer are accounted for to (a) improve building heat load calculations, (b) determine the important characteristics of existing (and new) buildings for infiltration heat loads, and (c) account more accurately for wind effects.

Comfort in an air-conditioned room depends to a high degree on the prevailing movement of air. As air velocities in excess of 0.1 m/sec can be regarded as draft phenomenon, a measuring device has been developed which will facilitate measurement to a sufficient accuracy and independent of any fluctuations in the air temperature even with low velocities.

Flow patterns at ground level in groups of buildings result from the complex interaction between the wind (impact, average speed distribution with height, and turbulence) and the buildings themselves (shapes, sizes, arrangements, etc.). The

This paper outlines the living conditions that can occur in the proximity of buildings and the significance of the wind velocities that can be established, for example for shopping centres when these include high-rise buildings or for patio schools when these are to be suitable for education in the open air. It also illustrates how natural ventilation in the building occurs and describes the influence of the wind on mechanical ventilation systems.

The typical infiltration load for a residential building has been found to range from one-third to one-half of the total space conditioning load. However, most infiltration measurements have been made on single-family houses. 

The multiple tracer gas technique developed at UMIST has been applied to the measurement of roof-space ventilation rates and house to roof-space air movement, for various types and combinations of roof-space ventilation. It has been shown that ridge tile ventilators, whilst increasing roofspace ventilation rates at low wind speeds, also significantly increase house to roof-space airflows over the whole range of wind speeds. This has implications not only in terms of energy wastage, but, more significantly , in terms of increased moisture rates to the roof-space.

For more than two years a series of detailed air infiltration measurements have been conducted over the complete yearly weather cycle on two identical side-by-side test houses in Gaithersburg, Maryland, USA. These measurements have been part of a broad study of the interaction of air infiltration , indoor air quality and energy in tightly constructed, well-insulated homes. The standard method of collecting air infiltration data throughout the study has been tracer gas decay. Operation of the duct air circulation fans has transformed each house into a single well-mixed cell .

The heat losses from small houses, due to transmission and ventilation, are estimated. The estimation i s based up on the house owness daily readings of electricity and water meters, and their notes on behaviour influencing the energy use. Consideration is taken to heat supply from insolation and from people. Hot water losses are calculated from use of water and use of household machinery. Besides the estimation of the heat losses, Q, wind and temperature in the area is registrated .

Describes a new procedure for predicting the thermal comfort of people in naturally ventilated buildings. The procedure starts by obtaining, for each important wind direction, velocity ratios between points of interest inside the proposed bu

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.