Numerical Analysis And Wind Tunnel Test Study On Aerodynamic Performance Of Wind Barrier-Train-Simply Supported Box Girder System

With the rapid development of high-speed railway, train speed is more and more fast, crosswind effect on the aerodynamic performance of train-bridge system is becoming significant,therefore, it is necessary to study the aerodynamic performance of train-bridge system under crosswind. With the help of FLUENT software and wind tunnel test,this thesis makes numerical analysis and experimental research on aerodynamic characteristics of train-bridge system when the bridge has wind barrier or not. The main contents and achievements of this thesis are as follows:(1)Numerical analysis on aerodynamic performance of wind barrier-train-simply supported box girder system is carried out. A3D model is established based on FLUENT which can consider interaction effect among wind barrier, train and simply supported box girder.Then aerodynamic force of the Train and box girder is calculated, and the effects of incidence angle, wind speed, the lateral position of train on the bridge, groupage train position, wind barrier shape and wind attack Angle on the train aerodynamic performance are discussed.(2)Wind tunnel test is carried out on aerodynamic performance of the wind barrier-train-simply supported box girder system. The test scheme and a wind barrier-train-bridge system model with scale factor of1:20is designed according to the object’s geometry shape, the similarity criterion, blocking ratio. Then, the aerodynamic force of train are measured based on Japanese JR3six component strain dynamic balances and the train aerodynamic force coefficients are calculated. Furthermore, the effects of the wind Angle, wind speed, the train horizontal position on the bridge, the train position, the wind barrier settings impacting on aerodynamic performance of the train are discussed, and compared with numerical results. The results show that the wind barrier on the bridge can decrease the train aerodynamic forces obviously, and the wind tunnel test match well with parts of numerical results.