Wind action on the building faсade and Its influence on ventilation heat losses

Authors: 

Bullová I.

Technical University of Kosice,
department of architectural engineering

A significant factor affecting of indoor climate and energy consumption in buildings is the air exchange rate. In correlation method is used mostly stationary outdoor climatic conditions specified in the standards - considering the constant value of the air exchange rate of nN  0.5 1/h, which is set in STN.
Great influence for air filtration and energy consumption has the total air pressure difference Δpc - creationed from influence of pressure difference from temperatures Δp and the wind Δpv. The air pressure difference is created at the interface between the internal and external environment. In real environment is the interface formed by buildings and their façade. From outside act the wind on the building the power expressed by external aerodynamic coefficients Cpe. Faсade shows a certain degree of the air permeability, which causes the interaction changes of external and internal pressure. Therefore we must also consider the size and dimension of the internal pressure coefficient Cpi, acting on the other side of the surface.
The paper is focused on the issue of non-stationary processes, causing a large variability of the air exchange rate and ventilation heat losses, with an emphasis on accurate aerodynamic coefficients used in the simulation methods. In the article were analyzed and quantified the results for selected factors – the layout, the proportion and size of the opening constructions in the façade - for the particular type of buildings in terms of space and height proportionality.

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