Atmospheric wind pressure distribution on an isolated agricultural silo / Distribuição da pressão atmosférica do vento em um silo agrícola isolado

Adrián Roberto Wittwer, Héctor Darío Mónaco, Jorge Omar Marighetti, Hugo Félix Begliardo, Mario Eduardo de Bortoli, Juan José Nittmann, Acir Mércio Loredo Souza


Storage silos installations are very common in the agricultural areas of Argentina and Brazil. Accidents caused by the action of the wind on the structural components of silos are usually reported. For this reason, the UTN - Regional Rafaela and the Laboratorio de Aerodinámica of the UNNE began to develop experimental studies in a wind tunnel with the objective of analyzing the external pressure distribution on isolated silos and complementing the procedures established in the Argentine Wind Code CIRSOC 102 and in the Brazilian Code NBR 6123. The tests were carried out in the UNNE “Jacek P. Gorecki” wind tunnel, which is a boundary layer tunnel of the Eiffel-type. The total length of the tunnel is 39.65 m, the test section is 2.4 m wide × 1.8 m high × 22.8 m long and an axial fan generates a maximum speed of 25 m/s. Turbulence generators and surface roughness elements were used to simulate atmospheric wind and then a 1:100 scale model of the silo was tested. In this work, results of mean and fluctuating pressure values obtained by wind tunnel tests are presented. The turbulent wind actions defined by the fluctuating pressures are evaluated through the distributions of RMS and peak values.


aerodynamic forces, wind tunnel, reynolds number.

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