Influência da vizinhança na determinação das pressões de vento em edificações com o uso de software CFD

Abstract

In the scope of structural engineering, wind is characterized as a variable load capable of causing harmful effects to buildings and being capable of leading them to collapse. Wind effects are especially dangerous when it comes to tall and/or slender buildings. Considering that air is a fluid and its flow is influenced by several factors – such as the presence of obstacles in adjacent areas, dimensions and shape of the building–, the present work aims to analyze the influence of different neighborhood conditions on the pressure values acting in a building. First, the effects caused by wind interaction with solid obstacles are explored, wind tunnel tests and CFD simulation for solving problems involving wind flow are discussed; in the sequence, the the normative methodology for the determination of wind forces in buildings is presented. In analysis, nine neighborhood configurations, common in urban centers, were modeled, followed by fluid dynamic analysis using an Autodesk CFD software. The results obtained were post-processed and represented in the form of velocity profiles and three-dimensional static pressure graphs. Lastly, each simulation was individually analyzed and two of the simulated cases had their results compared with the values obtained according to the procedure of NBR 6123/1988.