Investigates the effects of five different ventilation strategies on the annual energy consumption for heating and warm water of residential (family) homes. The strategies are: (1) natural ventilation, (2) mechanical ventilation and three forms of exhaust plants. Uses weather data from Portland, Oregon and Great Falls, Montana as examples of very different climatic conditions and heating/cooling requirements. The University of Wisconsin TRNSYS program was used for numerical simulation.
States that with improved thermal insulation, ventilation heat losses are becoming increasingly important for the total heat demand of a building, particularly multistorey buildings. Explains how the ventilation heat loss of individual rooms
The Heat Protection Ordinance (Warmeschutzverordnung EnEG) issued in 1977 aimed to reduce heating energy consumption and has become part of the building ordinances. Beside the heat transmission resistance (k-value-a measure for the size of the heat transmission losses), also the crack flow exponent (a-value) has been controlled to reduce ventilating heat losses. Practical experience has shown that, without mechanical ventilation, hygienic, physiological and building physical disadvantages will turn up.
Measurements of the radioactive subsoil inside a closed and air conditioned room were made to establish how far the concentration of radon and the radon daughters may be changed by means of ventilation. Whereas the radioactive subsoil in a building cannot be influenced due to the given cosmic radiation and the radio-active isotopes, it is generally assumed that the radio-activity originated by Radon 222 may be removed from the room air by ventilators. The radon diffusing from the brickwork disintegrates into several intermediate radio-active products and finally into stable lead.
The use of heating and ventilation was measured in several flats to find the relationship between the two. Measurements were taken in 9 flats in a 6-storey block in Berlin, with various types of ventilation system. Two flats remained uninhabited to serve as a comparison. The duration of the opening of windows of the individual rooms lastd on average up to 15 hours per day during the whole heating period. The tenants' own evaluation of the duration of airing differed immensely from this result.
This study deals with natural heat transfer through apertures between two adjacent rooms. A one-dimensional model has been developed to determine the flow rate and enthalpy rate transferred through each aperture as well as the vertical temperature profile in each room. Results show that flow rate and enthalpy rate vary quasilinearly through time. Temperature profiles show a high thermal stratification depending on the relative location of the apertures. Experiments have been performed in a test apparatus using water. Temperatures have been measured.
A mathematical model, CLIM, is used to compare constant air flow ventilation with adjustable ventilation controlled by indoor relative humidity. Exhaust air flow varies in a ratio of 1 to 4 between 40 and 75% of relative humidity and the mean annual air flow is divided by 2 in comparison with a classical mechanical ventilation system.
Introduces a new HVAC system which adapts the actual needed quantity of outside air and at the same time maintains the demanded thermal conditions. Apart from the temperature, the CO2-level in the controlled zones is used tocontrol the system. The new HVAC system is compared with a conventional one by computer simulation for annual energy consumption.
A gas sensor was used which measures the partial pressure caused by gases polluting the air. The sensor signal was measured in different rooms and compared with the pollution and CO2 rate in the air. The sensor can measure the air quality under various conditions and be used to control the fresh air volume, thus reducing ventilation heat losses.
Describes the instrumentation and measurement technique used by the CSTB to measure the leakiness of residential buildings. Results of the experiments are also presented.
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