A Simplified Model to Estimate Natural Ventilation Flows for
Simple Dwelling Layouts
Fernando
Marques da Silva and Jorge G. Saraiva
Laboratório
Nacional de Engenharia Civil,
Av.
do Brasil, 101; 1700-066 Lisboa, Portugal
Abstract
The paper presents a procedure
to estimate natural ventilation flow rates through buildings. The principle is
to assume that the flow paths are known and that the whole building is an
association of ducts that can be coupled either as series or parallel
configurations. The equivalent characteristic airflow vs pressure curve is then
established. The main driving force is the pressure difference on façades,
expressed via their respective
pressure coefficients, together with an appropriate reference wind velocity. A
thermal (stack) component may be added to establish the final pressure values. A
set of curves related to the variables involved is drawn in order to build a
four-quadrant graphical nomogram allowing for an easy application of the
procedure.
Key words: natural
ventilation, air flow, system characteristic, wind driven ventilation,
calculation method.
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