Uses wind tunnel model studies of houses to determine how best to reduce the surface pressure variations from wind and the associated air infiltration emphasizing the correct placement of suitably modelled coniferous trees. Finds that tree crowns convert the directed kinetic energy of approaching wind into random turbulent energy, which reduces pressure gradients on the windward walls, a prime region for air infiltration.
Describes two projects concerned with heat recovery in apartment buildings. Measures energy savings during normal operation when heat is recovered from exhaust air by a static flat-plate heat exchanger or by a heat pipe heat exchanger. Energy savings predicted during design stage are not achieved in practice because of inadequate system adjustment. Results show that energy savings can be calculated with good accuracy from individual measurements of temperature efficiency and supply air flow rates.
Describes methods for measuring air flow rates and air velocities in buildings, with the aim of formulating identical rules within the Nordic countries for the inspection and adjustment of ventilation systems.
Presents a review of the main methods used for the study of air movement. Includes sections on physical modelling (wind tunnel modelling etc), analogue (water and electrical) models of air movement, mathematical models and digital computer analogues, and full scale investigations including pressurization andtracer gas techniques.
Investigates the efficiency of models describing infiltration and natural ventilation in buildings. Considers 8 different models. The parameters of the models are determined by fit to data from 6 different ventilation experiments in residential buildings. The number of parameters in each model is varied and the effect of this on the model efficiency is evaluated. The effect of simple corrections of the models for a dependence on the wind direction is considered.
States that as many as 600 lung cancers a year may be attributable to radon gas, and this may jump to as many as 1500 if energy conservation measures reducing draughts become more widespread. Notes that radon appears to be present in every hou
Investigates excessive energy consumption in a house mechanical ventilation and heat exchanger. Explains why the house consumes so much energy. Analyses the ventilation system and defines a "coefficient of performance". Such a factor could characterise the energy requirement of a ventilation system. Emphasizes that the ventilation system is to be regarded as an entire system and that a certificate for the exchanger does not guarantee that the totalsystem will perform satisfactorily.
Notes that many air conditioning and industrial installations function inefficiently since too little attention is paid to air movement in a room. Compares effect of inlet and exhaust air devices. Considers reduced ventilation need if pollution can be eliminated or reduced. States that ventilation efficiency is an indication of how efficiently the air is used in the occupation zone and that the air supply to a zone determines ventilation efficiency. Illustrates various forms of ventilation.
Indicates that a systematic analysis is necessary if satisfactory results are to be achieved and suggests various stages of analysis. Provides practical examples with illustrations.
Indicates that 35-70% of a building's annual energy consumption is used by ventilation plant. Notes difficulty in determining which energy saving measures are most profitable but states that restricting fresh air supply tothat required is one measure that has not been considered and that most systems are designed for maximum capacity without facilities for varying load according to conditions. Describes plant which uses CO2-controlled ventilation in a sports hall. Illustrates circadian changes.