A two dimensional model was developed to predict the infiltration load to a cold room through its doorway. The governing equations were derived and transformed into dimensionless form. The model showed that the infiltration load to a cold room depends on three dimensionless parameters: the Grashof number of the cold room, the aspect ratio of the room (height to width), and the opening ratio (height of doorway to height of the room). 1\ finite difference technique with a control volume approach was used to solve the governing equations.
The energy statistics of OECD Countries shows that between 30-50% of primary energy is consumed in non-industrial buildings (i.e. in dwellings, offices, hospitals, schools etc.) Of this, as much as 50% is dissipated from the building in the departing air stream. As buildings become more thermally efficient, the proportion of energy loss (either heating or cooling losses) associated with ventilation and air infiltration is expected to become the dominant thermal loss mechanism. Additional losses may be associated with the energy needed to operate mechanical ventilation systems.
This study reports on the introduction of air infiltration and mechanical ventilationin a model for energy consumption estimation. The model applies to air conditionned nonresidential building and is developped to need few inputs. Existing air infiltration models arecompared and three equivalent leakage area (ELA) databases are tested on the same casestudy. Calculations of air input throught opened-doors are made to compare flows due to airinfiltration and due to natural ventilation. Simulations are made considering mean airinfiltration value and hourly values.
The research described in this paper is part of a project aimed at improving energy costs and the indoor environment of atrium buildings. Tracer gas techniques were used to assess the ventilation performance in terms of air distribution and contaminant migration patterns and to measure the air infiltration rate of a three-storey atrium. This atrium serves as an entrance to a large office-laboratory complex.
A Probabilistic model of air change rate in a single family house based on full-scale measurements has been developed. The probability of air change rate exceeding certain prescribed limits (risk of improper ventilation or excessive heat flow) is evaluated by utilising the distribution function based on calculated air flow rate. In this way the results are expressed in terms of the R-S model generally used in the safety analysis of structures.
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