A theoretical analysis of the fluid-solid interactions governing the removal of woody debris jams from cylindrical bridge piers
A theoretical analysis of the fluid-solid interactions governing the removal of woody debris jams from cylindrical bridge piers
复制标题
控制圆柱桥墩木屑堵塞清除的流固相互作用的理论分析
DOI：
10.1017/jfm.2019.1048
复制
发表时间：
2020
影响因子：
3.7
通讯作者：
Panici D
中科院分区：
文献类型：
--
作者：
Panici D
本文提出了一个理论模型来描述以前的实验室观测的碎片堆积的圆柱形桥墩周围的动态。该模型是基于这样的假设，即所观察到的动态主要是由施加在一个固体上的阻力的应用点的动态变化所形成的碎片积累在桥墩周围。所产生的非线性系统的常微分方程的相平面分析表明，该模型捕捉到的主要模式，在以前的实验室实验中观察到的，包括振荡运动和从桥墩的碎片的流动去除。该模型提供了一个理论基础的分析所需的条件，碎片堵塞，以保持稳定，在长时间的接触冲击流。也就是说，该模型表明，碎片积累的稳定性主要取决于几何不对称性和桥墩下游延伸的长度。前一个产生的扭矩需要旋转的码头周围的果酱，而后者产生的稳定效果后，身体旋转。
This paper proposes a theoretical model to describe previous laboratory observations of the dynamics of debris accumulations around bridge piers of cylindrical shape. The model is based on the assumption that the observed dynamics is mainly governed by dynamic changes of the point of application of the drag force exerted on a solid body formed by debris accumulated around a pier. A phase-plane analysis of the resulting nonlinear system of ordinary differential equations shows that the model captures the main patterns observed in previous laboratory experiments, including an oscillatory motion and the removal of debris from the pier by the flow. The model provides a theoretical basis for the analysis of the conditions required for debris jams to remain stable over long periods of exposure to impinging flow. Namely, the model indicates that the stability of debris accumulations primarily depends on geometrical asymmetry and on the length of the extension downstream of the pier. The former induces the torque required to rotate the jam about the pier, while the latter produces a stabilising effect after the body rotates.