Abstract:

With the intensification of chemical equipment, parallel towers are often damaged due to large cross-flow vibration. However, the coupling mechanism among parallel towers is complex, which is rarely reported. In order to solve this problem, a rigid truncated model with elastic support was used to simulate the cross-flow vibration of parallel towers, and wind tunnel experiments were carried out to analyze the cross-flow vibration characteristics. The cross-flow displacement of each tower was measured, and the cross-flow vibration characteristics of the parallel towers were analyzed. In addition, a micro fins were designed, and the best vibration reduction effect was achieved by adjusting the size parameters of micro fins. The research showed that the cross-flow vibration characteristics of parallel towers can be divided into three typical regimes according to the range of spacing ratio, which contains "single bluff body" regime, "reattachment" regime and "co-shedding" regime. When spacing ratio S/D<2, the upstream tower will gallop at a smaller reduced velocity, and there will be energy conversion between upstream and downstream towers, which should be avoided in engineering practice. When the thickness parameter of micro fins is greater than 0.1D and the length parameter is greater than 0.9D, the vibration reduction effect of micro fins is the best, which can prevent wake galloping and reduce the cross-flow amplitude of parallel towers by 78.63%—95.67%.

Key words: parallel towers, wind-induced vibration, micro fins, vibration reduction, fluid mechanics

摘要：

随着化工设备集约化，并排塔器因大幅横风向振动而发生破坏的现象时常发生，然而各塔器间的耦合机制复杂，少有报道。为了解决这一问题，本文应用弹性支撑的刚性截断模型模拟并排塔器的横风向振动，开展了风洞实验，深入分析了并排塔器的横风向激振特性；设计了一种微型翅片，通过调整尺寸参数达到了最佳减振效果。研究结果表明，并排塔器的横风向激振可按照间距比范围分为三种典型振动状态，即单钝体模式、剪切层再附着模式和共同脱涡模式。当间距比S/D<2时，上游塔器在较小的折合流速下即发生驰振，且与下游塔器存在能量转化，在工程中应予以避免。当微型翅片的厚度参数大于0.1D及长度参数大于0.9D时，微型翅片的减振效果最佳，可以防止尾流驰振，使并排塔器的横风向振幅减小78.63%~95.67%。

关键词: 并排塔器, 风致振动, 微型翅片, 减振技术, 流体力学