| Reform and opening up has contributed to the rapid development of my country’s national economy in the past two to three decades.Opportunities and challenges have sprung up along with urbanization.High-rise buildings have sprung up,and super high-rise buildings and large-span structures have continued to emerge.The era will continue to develop,and urbanization will not stagnate.It is expected that in the near future,high-rise buildings and large hip space structures will move to a higher level,but the accompanying problem is that the scale of the structure is getting larger and larger,which will inevitably lead to the structure becoming soft and soft,which is obviously not conducive to the structure.Stable,people are gradually aware of the rapid development while ensuring the safety and comfort of the structure.Wind load has become an important factor in controlling the reliability,comfort and safety of these wind-sensitive structures.Aiming at the wind-induced vibration problems of square column structures that are common in practical engineering,this paper takes the square column as the main research object.The flow field around the structure is changed by arranging a collar with openings on the surface of the square column.CFD numerical simulation is combined with theoretical analysis.,Study the passive self-blowing flow control method that suppresses the square column wake and wind-induced vibration effects.Under Re=22000,the large eddy simulation of the flow around the square cylinder was used to perform CFD numerical simulation,and the grid independence and time step independence were verified.The aerodynamic parameters and wake field characteristics of the square cylinder model surface were calculated and compared with the previous Human experiments and numerical simulation results verify the accuracy of large eddy simulation.On this basis,by comparing and selecting the aerodynamic characteristics of the column surface under three different angle-cutting conditions,the optimal angle-cutting scheme is determined,which lays the foundation for subsequent numerical simulation research.The passive jet flow control method is adopted to simulate the fixed flow around a three-dimensional square column.Under Re=50000,the large eddy simulation of the square column-ring 2.5D segment model is used for CFD numerical simulation to determine the height of the ring,the radial thickness,the number of openings and the opening height,and the aerodynamic force of the ring square column segment model And the influence la w of wake vortex off mode,by comparing with the aerodynamic force and wake vortex off mode of an uncontrolled square column(without the ring),the optimal ring control parameter combination is obtained.On the basis of the optimal collar parameters,the control effect of passive self-blowing collars under different wind speeds and different wind angles on the fixed flow around a three-dimensional square column is studied,and it is proved that the control methods of passive self-blowing collars are different.Validity under conditions.The span-wise layout spacing between the collars was changed,and the effects on the three-dimensional square column aerodynamic force and wake flow field were compared to obtain the optimal span-wise layout spacing.The passive jet flow control method is used to simulate the cross-wind vortex-induced vibration of the square column under the mass-spring-damping system.Combining the UDF and the dynamic grid method,the cross-wind vibration of a single-degree-of-freedom square column around the flow is studied,the fluid-solid coupling between the uncontrolled square column and the cross-wind direction around the flow field is realized,and the locking interval and the common amplitude value are obtained.Finally,under the opt imal collar control parameter combination,the research of the passive jet flow control method for the control effect of the vortex-induced vibration around the square column is completed. |
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