Numerical simulation of wind-induced vibration characteristics of square-section high-rise buildings

In this study，a square-section high-rise building with width to height ratio of 1∶6 was regarded as the research object.The Navier-Stoke equation of incompressible viscous fluid is solved based on the RSM model by using the computational fluid software FLUENT. The vibration response of the structure was solved by Newmark-β method（connected by user-defined function of FLUENT），thus researching the wind-induced vibration of the structure characteristic. Then，the flow field around rigid staticmodel and aeroelastic model was studied. The results showed an obvious phenomenon of displacement‘locking in’happened in high-rise buildings，which was in good agreement with the wind tunnel test results. In the velocity profiles，the change rule of displacement response was related to the average wind speed of the flow field. When the average wind speed was close to the locked wind speed，the displacement response of the structure was most obvious. With the increase of the wind speed，the structure presented first and second order wind-induced vibration respectively. The flow field around high-rise structures had obvious three-dimensional characteristics. Along the height of high-rise building，the development of vortex was unbalanced. The closer it was to the bottom，the shedding vortex was asymmetric，and the closer it was to the top，the shedding vortex was symmetric. And its change rule was related to the velocity distribution of the flow field.