ABSTRACT
The Venturi-effect refers to the increase of fluid speed due to a decrease of the flow section. Although it was originally defined for confined flows, in the past the use of this terminology has been extended to wind flows in passages between buildings, which are non-confined or open flows. In this paper, the wind speed conditions in converging and diverging passages between perpendicular buildings are studied with Computational Fluid Dynamics. The aim is to investigate the extent to which the Venturi-effect contributes to the increased wind speed in the passages. The simulations show that the wind conditions are systematically more severe in diverging than in converging passages, which is opposite to what is generally assumed. It is shown that the term Venturi-effect should be used with caution in building aerodynamics and that it is not always suitable to describe wind flow in passages between buildings.
