Numerical sulation of arodynamic drivatives of box girder with CFD method
Liu Yue1; ZHANG Zhi-tian2; CHEN Zheng-qing2
1.China Northwest Municipal Engineering Design and Research Institute CO.,LTD. Wuhan, 430056，2. Wind Engineering Research Center, Hunan University，Changsha，410082，China
Abstract：Aerodynamic derivatives of a thin flat plate and a bridge girder section are recognized through forced vibration method in wind tunnel and CFD dynamic meshing simulation, respectively. Results indicate that, with the case of the stream line section, numerical results of CFD simulation are in good agreement with those obtained by wind tunnel test. In the case of box girder section there exists some obvious discrepancy between CFD numerical simulation and wind tunnel test, characterized by two errors in low reduced wind velocities and large errors in high reduced wind velocities. In order to increase the precision of CFD identification of aerodynamic derivatives for bluff sections, refined spatial grid and prolonged computing time are needed at the expense of precious computing time. Thus, a conspicuous disadvantage exists in the present CFD numerical method in the identification of aerodynamic derivatives of bluff girder sections, especially the stability and efficiency of the CFD algorithm. In the view of this, the CFD method cannot supplant the physical wind tunnel test for the moment when the fluid-structure interactions of blunt bridge section are involved.
2011, Vol. 30 
