【摘要】：當橋面接近地面時,地面的存在會使斷面的繞流情況與遠離地面時不同,有可能對主梁在風荷載作用下的靜力和動力響應產(chǎn)生不利的影響,而主梁離地高度將成為影響主梁氣動性能的重要因素�；陲L洞試驗和計算流體動力學(CFD)相結(jié)合的方法,對存在地面效應的近流線型斷面的渦激共振性能進行研究。首先,基于風洞試驗獲得近流線型斷面在兩種粗糙度地面、三種風攻角、四種離地高度下的渦激共振區(qū)間和振幅及其隨離地高度的變化規(guī)律,試驗結(jié)果表明,地面效應會使得渦激共振區(qū)間提前但渦激共振幅值有所減小。其次,采用CFD識別各試驗工況下的斷面的繞流特征、鎖定區(qū)間和最大振幅,并通過靜態(tài)和動態(tài)流場可視化分析,分析了地面效應對近流線型斷面渦激振動的影響機理。
[Abstract]:When the bridge deck is close to the ground, the presence of the ground will make the flow around the section different from that when the bridge is far from the ground, which may have a negative effect on the static and dynamic response of the main beam under the wind load. The height of the main beam from the ground will be an important factor affecting the aerodynamic performance of the main beam. Based on the method of wind tunnel test and computational fluid dynamics (CFD), the vortex-induced resonance of near-streamline cross-section with ground effect is studied. First of all, based on wind tunnel test, the vortex-induced resonance region and amplitude of near-streamline section at two roughness ground, three wind attack angles and four different heights from the ground are obtained. The experimental results show that, The surface effect will make the Vortex resonance range advance but the co-amplitude of vortex-induced resonance decrease. Secondly, CFD is used to identify the characteristics of cross-section flow under different test conditions, and the maximum amplitude and interval are locked. The mechanism of the effect of ground effect on vortex-induced vibration of near-streamline section is analyzed by visual analysis of static and dynamic flow fields.
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本文編號：2182289