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 transient simulation method TRATMO with applications to the analysis of the hygrothermal behaviour of timber frame constructions with additional thermal insulation is discussed. This method makes it possible to evaluate the hygrothermal behaviour with respect to risks of mouldering since it gives simultaneous information on moisture content and temperature at certain sections of the construction. Based on the computer simulations and experiments a number of practical aspects to be considered in additional thermal insulation of timber frame constructions are introduced.
The thermal effects of air flows in building structures have been analyzed by computer simulation. Some laboratory experiments have also been carried out concerning natural convection in closed and semi-open cavities filled with fibrous insulating material. Three different flow systems in building structures have been studied: natural/forced convection in open/semi-open (permeable cold surface) 2-dimensional insulation structures, heating of infiltrating air in cracks and diffusive infiltration.
A method has been introduced for the analysis of the hygrothermal behaviour of building materials and construction. The model equations for coupled heat and mass transfer used in the computer code TRATMO and in the determination of hygrotherm
A method to analyze thermal and moisture physical behaviour of building components under transient conditions is introduced. The method is supported by the procedure TRATMO (Transient Analysis of Thermal and Moisture Physical Behaviour of Constr
An analysis of ventilation necessary to maintain air quality in an above-ground fallout shelter was done, making use of theoretical models, and generalizing the results to fit measurements on actual shelter data. Results show that, at most, boundary surface heat loss serves as a safety factor for ventilation systems, and thus ventilation systems should be designed to remove the entire thermal load generated within the shelter. This, when considered in addition to weather and load expectations, establishes an upper limit on ventilation equipment size.
Ventilation and air exchange in buildings and industrial plants can be induced by external winds and by buoyancy forces. The dependence of the air exchange and heat transfer on a large number of factors, including the detailed configuration of the building and surroundings makes an analytical or numerical analysis of practical design problems impractical, particularly when both the buoyancy and the wind-induced pressures are of the same order of magnitude.
With correct application of vapour barriers the ventilation of building structures is in general not necessary, unless such barriers prevent the escape of trapped moisture from moisture-sensitive - especially organic - materials. Indoor and outd
In this paper, an empirical method is proposed which qualifies the thermal performance of buildings through the entire year. The thermal quality parameter (BTPI) is intended to be an instrument for the implementation of new energy regulations for buildings, especially for those that are located in areas with mild climate and no heating or air conditioning systems. Portuguese climatic zones are typified for summer and winter and predominance factors for seasonal loads are defined.
This paper presents a mathematical model, implemented in a general computer code, that can provide detailed information on the velocity and temperature fields prevailing in three-dimensional buildings of any geometrical complexity, for a given v
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