Full-scale study of conical vortices and their effects near roof corners

Investigations of wind-induced building damage have shown that roof and roofing systems are the most vulnerable parts of the whole building envelope to fail, and damages to the roof typically initiate around the roof comers and edges where extremely high suctions occur because of the flow separation. It is known that the high suctions near the roof comers and edges are mainly induced by a separated flow phenomenon — conical vortices.

Full-scale experiments were conducted at Wind Engineering Research Field Laboratory (WERFL) of Texas Tech University with the aim to understand the mechanism for generation of conical vortex flow and the associated high roof surface suctions. A synchronized data acquisition system was set up on the roof of the experimental building at WERFL to simultaneously collect conical vortex images and the data of approaching wind and roof comer suction pressures. Extensive flow visualization and pressure measurement experiments were carried out, and over 100 reliable 15-minute data runs were collected. These vortex-image-synchronized data were subjected to systematic analyses to improve our understanding of this conical vortex flow phenomenon.