Estudo da influência de obstáculos na dispersão de gases para classificação de áreas de risco utilizando fluidodiâmica computacional.

Abstract

In this work, the effect of obstacle radius and distance from a pressurized fuel gas emission source has on the extension and volume of the flammable gas plume along the measurement axis evaluated via Computational Fluid Dynamics (CFD). The study of obstacles is an object of interest in hazardous area classification, given that little is reported in the international standard IEC60079- 10-1:2015. The results of this study are important on hazardous area classification where an explosive atmosphere can be form, these classifications are regulated by the IEC6007:10-12015 standard. ANSYS CFX 16 software was used on the computational simulations. The influence of the jet velocity profile was also observed in relation to the position and radius of the obstacle, it was verified that if the maximum jet velocity has not yet been reached, another jet profile can be generated, changing the dispersion and its approach. It was observed that the obstacle breaks the moment of the jet, decreasing the dilution of the gas with ambient air and, as a consequence, depending on the conditions of distance and radius of the obstacle in question, increasing or decreasing the gas plume and its extension along the surface. of the obstacle. Finally, a mathematical model was generated for the extension and volume for the given concentrations, which can be used in the future as a basis for hazardous area classification.