Aerodynamic control of Long span Bridges

该研究计划将对柔性安装的桥面模型的稳定性和抖振响应进行CFD和风洞试验。驾驶台甲板将安装摆动襟翼类型的气动操纵面。桥面上的传感器、数字控制系统和襟翼的电气驱动将被用来增加桥梁在升沉-扭转模式下的稳定性。首先将使用准三维CFD计算颤振边界。颤振开始的临界风速将根据不同亚临界风速下的响应来评估。还将计算系统对指示控制面移动的响应，并将结果用于桥梁建模，首先是一段桥面，然后是一座完整桥梁的三维模型。将对一系列桥梁参数进行测量，包括桥面几何形状和平滑/湍流入射风向，以评估该系统在提高全尺寸悬索桥和斜拉桥的临界颤振速度和减轻抖振和涡激振动方面的有效性。这些试验也将用于验证数值结果。

The research program will carry out CFD and wind tunnel tests of the stability and buffet response of flexibly-mounted bridge deck models. The bridge decks will be fitted with aerodynamic control surfaces of the oscillating flap type. A combination of sensors on the deck, a digital control system and electrical actuation of the flaps will be used to increase the bridge stability in the heave-torsion mode. Quasi-three-dimensional CFD will be used first to compute flutter boundaries. The critical wind speed for flutter onset will be evaluated from the responses at different subcritical wind speeds. The system response to indicial control-surface movement will also be computed and the results used to model bridges, first on a section of the deck and later on a three-dimensional model of a full bridge. Measurements will be made, for a range of bridge parameters including deck geometry and smooth/turbulent incident winds, to assess the effectiveness of the system in increasing critical flutter speeds and alleviating buffeting and vortex-induced-vibration for full scale suspension and cable-stayed bridges. These tests will also be used to validate the numerical results.