The International                        UPDATED 22nd May 2011
Journal of Ventilation
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June 2011 Edition of the IJV now Published  Call for Papers

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Paper 6:  Volume 5 No.1 June 2006 Edition

Impact of Internal Pressure Coefficients on Wind-Driven
Ventilation Analysis

P. Karava, T. Stathopoulos and A.K. Athienitis

Centre for Building Studies, Department of Building, Civil and Environmental Engineering,
Concordia University, Montreal, Quebec, Canada

Abstract

Internal pressure coefficients in a building with wind-driven cross-ventilation caused by sliding window openings on two adjacent walls are presented and compared with previous works. The study found that internal pressure coefficients vary considerably with the opening area (or wall porosity) and the inlet to outlet ratio. The internal pressure is not uniform in a building with cross-ventilation, particularly for large openings (wall porosity higher than 10%). For inflow calculation, the average internal pressure coefficient should be used as an input in the orifice equation. The paper investigates the main parameters affecting natural ventilation, particularly cross-ventilation design. The impact of internal pressure coefficients on airflow prediction is significant.

Key words:  Cross-ventilation design, inlet to outlet ratio, internal pressure coefficient, wall porosity, wind-driven flow.

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