Studies the direct coupling of ventilation heat and solar gains to increase the performance of passive solar systems. Examples of particularly suitable buildings are described. The thermal model FRED, based on a thermal resistance network representing a three-zone building, is modified to include a simple airflow model driven by wind speed and temperature difference. The simulated building is ascribed symmetric permeabilities, then asymmetric permeabilities.
Describes the pollutant burdens on indoor air. Notes heat exchanges by air renewal and associated heat losses. Examines how to determine the required air change rate. Lists the minimum air changes for various types of building with and without smoking. Treats air infiltration. Considers how to reduce losses with air renewal by weather stripping, special air inlets, reduction of the indoor air temperature, heat recovery with controlled mechanical ventilation, heat pumps and heat pipes.
Energy consumption due to ventilation and air infiltration has been estimated to be 30-50% of the total energy use in Finnish high rise residential buildings. While natural ventilation was common in earlier buildings, central mechanical ventilation systems have become predominant during recent decades. Presents a typical energy balance in an apartment building. The heat loss due to ventilation and infiltration appears to be 0.5-0.7 ach.
Describes work carried out by British Gas to establish the magnitude of heat losses from gas-fired boilers arising from natural ventilation through the boiler during its shutdown period. Discusses the general principles of ventilation heat losses to the flue and via the draught diverter and presents data for heat loss decay rates for a range of boilers. Calculates ventilation heat losses for typical boilers. Concludes that for a typical open-flued domestic heating boiler, ventilation heat losses are approx 6% or less of total heat input.
Lists the HOTCAN computer program devised for use in the Division of Building Research (NRC) program on low energy houses. It is written in BASIC and is capable of estimating the space heating requirements of residences. Gives basic equations and assumptions, and weather data required, along with a listing of the program and a sample run.
Treats the relation between transmission heat loss and ventilation heat loss of buildings. Notes normal methods of fresh air ventilation of dwellings and problems arising with buildings being made increasingly airtight so that air infiltration is greatly reduced with consequent condensation and lack of maintenance of minimum hygiene standards. Illustrates and discusses possible future ventilation systems including mechanical supply and extract ventilation systems incorporating heat recovery systems. Illustrates several alternatives diagramatically.
Treats the research programme initiated by the Ministry of Research and Technology with the aim of achieving a more rational use of energy in dwellings by air conditioning and ventilation measures. Points out that domestic heating is responsible for around 40% of energy consumption in West Germany, of which about one third is dissipated as ventilation heat loss.
Describes a mathematical model for the detailed calculation of ventilation losses in buildings. The model takes account of the prevailing wind and buoyancy forces, the leakiness of the building facades and internal doors and the effect of exhaust installations. Derives a simplified calculation method for practical calculations by heating engineers which is applied in the new SIA Recommendation 384/2 "Heat demand of buildings".
Describes experiments carried out in 4 low energy electrically heated houses incorporating extra thermal insulation and heat recovery mechanical ventilation systems. Airtightness was made an objective so that the ventilation system would provide as much of the required fresh air as possible. Instrumentation was installed during construction to monitor the performance of the houses, with the cooperation of eventual purchasers. The houses were leak tested and sealed where necessary.
Login