Study of aeroelastic interference effect among four cylinders arranged in rectangular configuration

0510728 - ÚTAM 2020 RIV CZ eng C - Konferenční příspěvek (zahraniční konf.)
Hračov, Stanislav - Macháček, Michael - Michálek, Petr
Study of aeroelastic interference effect among four cylinders arranged in rectangular configuration.
Proceedings of Computational mechanics 2019. Plzeň: University of West Bohemia, 2019 - (Adámek, V.; Jonášová, A.; Plánička, S.; Zajíček, M.), s. 76-79. ISBN 978-80-261-0889-4.
[Conference with international participation Computational mechanics 2019. Srní (CZ), 04.11.2019-06.11.2019]
Grant CEP: GA ČR(CZ) GA19-21817S
Institucionální podpora: RVO:68378297
Klíčová slova: aeroelastic interference * flow structure interaction
Obor OECD: Civil engineering

The paper describes the analysis of the destructive oscillation of a skewed steel rod with the length 21 m. The steel rod is a part of roof supporting bundle (rectangular array) of cylindrical hangers at the airport building, it is therefore exposed to frequent moderate and sometimes strong winds with the low turbulence. The vibration is analyzed from the aeroelastic perspective, i.e. the cause of the oscillation is analyzed as wake-induced vibration because the collapse was observed at the bottom downwind hanger in that array configuration. The normalized distance of hangers in horizontal and vertical directions is equal to 3.15D, and 3.8D, respectively, where D is the diameter of the hanger cross section. Experimental testing of 1:1 scaled sectional model of four-cylinder array in the wind tunnel indicates, that the cause of the high level vibration is most probably the interference galloping. The unstable behavior was detected both for the downwind hanger as a part of rectangular array and for the hanger as a part of a two hangers in a row only. The results indicate the strong influence of the top pair of the hangers on the decrease of the critical wind velocity, which is even below the value of the critical wind velocity obtained for two hangers only. The strong hysteresis effect resulting in the preservation of the high vibration amplitudes even after the decrease of wind speed far below the critical one, was observed.
Trvalý link: http://hdl.handle.net/11104/0301121