The problems associated with the measurement of ventilation rates and air movement patterns in large single cell buildings which were unoccupied and unheated were investigated using the tracer gases nitrous oxide and sulphur hexafluoride.
A report from the research and development programme Domestic Ventilation is presented. Describes quantitative and qualitative experimental investigations in two flexible test houses of identical size, structure and thermal insulation to compare various ventilation installations and devices under natural weather conditions. The comparative criteria were air infiltration rates and air change, ventilation heat losses, operational behaviour, possible requirement of auxiliary energy, problems and weak points.
Notes the trend to installing windowless kitchens, bathrooms and W.C.s in the internal zones of dwellings. Describes a research project to measure for internal kitchens the energy consumption and emission of equipment, the total daily energy consumption, air temperatures, air humidity values during cooking, comfort and air speed. Illustrates the test kitchen and gives the results of measurements of around 100 days of simulated operation for a household of four. Notes the consequences for recommended normal and peak ventilation rates.
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.
Wind pressures on three Navy buildings at the Kanehoe Marine Corp Air Station, Hawaii were measured. Indoor and outdoor variables were also measured including temperature, dry bulb, wet bulb, relative humidity, wind speed, and wind direction. Pressure measurements were carried out using Validyne DP103 pressure transducers, and a static pressure probe. Natural ventilation is estimated 1. by combining window areas and pressure coefficients with wind speed and 2. using the LBL infiltration model.
Shows the results of a study of the effects of turbulence upon ventilation. Controlled fluctuating air flows were directed upon openings in the side of acube simulating a building. The relationship between the turbulent characteristics of the air flow and the ventilation rate in the building modeare examined. Mean windspeed and the turbulent velocity and intensity of the air flow were measured with a thermocoupled anemometer. Resulting ventilation rates were measured by means of tracer gas decay, using CO2 as the tracer and an infra red analyser to monitor the decrease in concentration.
A livestock building for 30 cows in loose housing was constructed in 1982. In the cow stable natural ventilation is provided through openings along the eaves. New types of inlets and outllets have been designed for natural ventilation systems. The regulation system for the air flow rate is a modified P-type regulator. Using timesharing of the regulation function, the inlet areas can be regulated in groups by means of four different temperature sensors in the building.
States that current building regulations on ventilation are very inadequate. Describes the Scottish Development Department document The future of building control in Scotland. This proposes a local authority liaison committee with reps from building control and fire services to co-ordinate work on operating building control in Scotland. It also recommends approval of standard house types of different conditions between authorities. Suggests this could usefully be introduced to England and Wales.
After a brief treatment of the ideas and aspects that play a role in ventilation, gives a general outline of chosen investigation methods, with a concise review of apparatus and calculation models used. Presents a review of the ventilation investigations carried out by IMG-TNO during the last 10 years in factories, labs, hospitals, auction halls etc.
Energy is consumed in heating the air infiltrating into houses maintained at temperatures above ambient. By using climatic data tapes and a daily profile for indoor temperature of a house, it is possible to calculate factors, which in conjunction with a relationship between air change rate and wind speed enable the energy consumption due to infiltration to be calculated on amonthly basis. This has been done for Melbourne, Australia and the factors tabulated on a monthly, annual and heating season (April Nov) basis.
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