Flight of Urban Windborne Debris

在风暴期间，风吹的碎片（屋顶瓦片，树枝）占破坏的10%至30%。EPSRC以前的一个项目资助了一名博士生研究单个碎片的自由飞行。https://doi.org/10.1016/j.jweia.2012.07.011该项目的目的是通过观察多个物体的飞行，在城市环境中和周围移动，在碎片损害链中发挥作用，来扩大这一范围。将采用风洞和计算流体动力学（CFD）建模相结合的方法。在前者中，将使用基于吸力的触发器从目标建筑物释放多个屋顶瓦片，并使用高速摄像机在城市环境中进行跟踪。将对同一情景进行计算流体动力学模拟，对碎片采用“智能”粒子跟踪，对发射和撞击阶段采用重叠网格。瞬时力和力矩系数将从以前的工作中推导出来。早期的项目已经开发了风中细长结构的风险模型（皇家学会IC 170137），并将其扩展到本地住宅（GCRF）。拟议的项目将利用碎片撞击位置和撞击能量的预测分布，扩大这一风险模型，以考虑风载碎片。

Windborne debris (roof tiles, branches) accounts for anywhere between 10 and 30% of the damage during windstorms. A previous EPSRC project funded a PhD student to look at the free flight of single items of debris https://doi.org/10.1016/j.jweia.2012.07.011. This project aims to extend that by looking at the flight of multiple items, moving in and around the urban environment, playing their part in the debris damage chain. A combination of wind tunnel and computational fluid dynamics (CFD) modelling will be utilised. In the former, multiple roof tiles will be released from a target building using a suction-based trigger and tracked using high speed cameras through an urban environment. CFD simulations will be run of the same scenario, employing "smart" particle tracking for the debris and overset meshes for the launch and impact phases. The instantaneous force and moment coefficients will be derived from the previous work. Earlier projects have developed a risk model for slender structures in wind (Royal Society IC170137) and extended it to vernacular housing (GCRF). The proposed project will use predicted distributions of debris impact position and impact energy to extend this risk model to account for wind borne debris.