脱硫排烟一体式钢塔TMD减振效果分析

Analysis of vibration reduction effect of tuned mass damper for desulfurization and exhaust smoke integrated steel tower

摘要:

发电厂中新型脱硫排烟一体式钢塔属于复杂的高耸薄壁结构,由于顶部截面突然变细,风荷载作用下极易产生较大振动,为了减小风致振动,提出了适用于脱硫排烟一体式钢塔的调谐质量阻尼器（tuned mass damper, TMD）减振方案.基于流固耦合理论,建立了结构场与流场计算模型,成功利用数值风洞方法计算了有无TMD结构的风振响应,并通过现场风振监测对数值方法的可靠性进行了验证.结果表明,该脱硫排烟一体式钢塔振型以局部或整体的平动、转动、屈曲与扭转为主,通过在塔体顶部设置TMD,位移动力响应最大值降低41%,均方根值降低75%.频谱分析表明,结构安装TMD后部分低频振型被激起,同时主频率对应的动力响应大大降低,TMD对于该脱硫排烟一体式钢塔可以起到较好的减振效果,为类似高耸薄壁结构的风振控制提供了参考.

Abstract:

In power plant, the novel desulfurization and exhaust smoke integrated steel tower is a complex high thin-walled structure. With the top section suddenly becomes thinner, the steel tower is prone to vibration under wind loads. To reduce the wind-induced vibration of the structure, a tuned mass damper (TMD) vibration reduction scheme suitable for desulfurization and exhaust smoke integrated steel tower was proposed. Based on the fluid-structure interaction theory, structure field and flow field models were established. Wind vibration responses of the structure with or without TMD were calculated by using a numerical wind tunnel method, and the method was verified by on-site wind vibration monitoring. Results show that the vibration modes of the integrated steel tower were mainly local or overall translation, rotation, buckling and torsion. By installing a TMD on top of the tower, the peak value of the displacement dynamic response was reduced by 41% and the RMS value was reduced by 75%. Spectrum analysis results show that the low-frequency component of the structure was excited after installing TMD, and the dynamic response of the main frequency was greatly reduced. Vibration reduction effect was obvious for the desulfurization and exhaust smoke integrated steel tower with TMD, which provides a reference for wind-induced vibration control of similar structures.