中央稳定板提高颤振稳定性能的细观作用机理

Micro-mechanism of a central stabilizer for improving a bridge's flutter stability

通过CFD数值模拟以及PIV风洞试验研究了中央稳定板对矮寨桁架梁悬索桥断面绕流的细观作用机理。CFD数值模拟表明中央稳定板促进了在桥面中央附近形成位于上下桥面的旋涡对,使之相当于升力的作用。有稳定板断面前端和尾部的旋涡体积增大,进而使桥梁断面在颤振中的竖向自由度参与作用增强。PIV流迹显示气流在中央稳定板的背风侧形成了漩涡,在模型尾部同样有旋涡的形成,进一步验证了CFD数值模拟的正确性。

CFD numerical simulation and PIV wind tunnel tests were conducted to study the micro-mechanism of a central stabilizer for a flow around Aizhai truss suspension bridge cross-section. CFD numerical simulation showed that the central stabilizer promotes the formation of vortex pairs at the upper and lower deck near the center of the bridge deck and makes them be equivalent to the action of lift force; vortex volumes of front and tail of central stabilizer grow to enhance the participation function of the vertical DOFs of the bridge cross-section in flutter. PIV flow trace indicated that the air flow on the leeward side of the central stabilizer forms vortexes, the same vortex formation occurs at the end of the bridge model, the correctness of CFD numerical simulation is verified.