Aerodynamics of low-rise buildings in atmospheric turbulence

在加拿大和世界各地，由于严重风暴造成的经济和保险损失继续增长。今年夏天的飓风摧毁了加勒比海几个岛屿的基础设施，突显了事关重大的问题。在严重的风暴中，建筑物的大部分损坏是房屋，而房屋是最常见的结构。覆层系统和屋顶组件特别脆弱，并指出，单一屋顶板的失效可能会导致雨水进入造成重大损失。对于像飓风这样的大范围风暴，利用比例模型的边界层风洞来确定作用在建筑物结构系统上的风荷载的方法已经建立得很好。然而，获取建筑构件(如覆层系统)的风荷载的方法仍未解决。对于龙卷风，不同的社区在设计中才刚刚开始考虑，尽管需要设计指导，但对建筑空气动力学知之甚少。*申请人研究计划的长期目标是减轻极端风对建筑物，特别是房屋的影响，以减少与这些风暴相关的损失，造福所有加拿大人，事实上，造福于世界各地的人们。与这项提议有关的短期目标涉及解决有关获得建筑部件和覆层系统上的风荷载以及龙卷风中的风荷载的空气动力学问题。建议研究的事项包括：(I)风相对于屋顶表面的垂直迎角；(Ii)迎面而来的气流中的漩涡；(Iii)湍流强度和尺度；以及(Iv)建筑物边缘的几何形状。在飓风(和其他大规模风暴)中处理建筑部件和覆层系统上的风荷载，以及在龙卷风中处理风荷载，需要解决许多相同的问题。特别是，需要并将开发将在一个特定湍流风场中获得的数据修改或校正为适合另一个特定湍流风场的数据的方法。这方面的一个例子是应用一种方法，将飓风期间在大气边界层中获得的风荷载修正为类似风速的龙卷风会发生的情况。*研究方法包括利用同时使用粒子图像测速仪和表面压力测量的边界层风洞实验。六名研究生和五名本科生将通过拟议的研究，在协作的国际小组环境中使用世界级研究基础设施进行培训，并有机会发展技术研究技能、沟通技能以及领导力和教学机会。

Economic and insured losses due to severe storms continue to grow, both in Canada and around the world. The hurricanes this past summer, which destroyed the infrastructure on several Carribean islands, emphasize what is at stake. The majority of the damage to buildings in severe wind storms is to houses, which are the most common structures. Cladding systems and roof components are particularly vulnerable, noting that the failure of a single roof panel can lead to significant losses because of rainwater entry. For large-scale storms such are hurricanes, methods for determining the wind loads acting on the structural systems of buildings using boundary layer wind tunnels with scale models are well established. However, methods for obtaining wind loads for building components such as cladding systems are still unresolved. For tornadoes, which are just beginning to be considered in design by various communities, little is known about the building aerodynamics even though design guidance is needed.***The long-term objective of the applicant's research program is to mitigate the effects of extreme winds on buildings, particularly houses, in order to reduce the losses associated with these storms, for the benefit of all Canadians and, in fact, people around the world. Short-term objectives associated with this proposal are related to resolving aerodynamic issues with respect to obtaining wind loads on building components and cladding systems as well as wind loads in tornadoes. Issues to be examined in the proposed research include how the following affect wind loads on buildings: (i) vertical angle of attack of the wind relative to the roof surface, (ii) vortices in the oncoming flow, (iii) turbulence intensity and scales, and (iv) the geometry of the building edges. Dealing with wind loads on building components and cladding systems in hurricanes (and other large-scale storms) and wind loads in tornadoes require that many of the same issues be resolved. In particular, methods to modify or correct data obtained in one particular turbulent wind field into those appropriate for another are needed and will be developed. An example of this would be applying a method to modify wind loads obtained in the atmospheric boundary layer during a hurricane into what would happen if it were a tornado of similar wind speeds.***The research methods involve boundary layer wind tunnel experiments utilizing simultaneous particle image velocimetry and surface pressure measurements. Six graduate students and five undergraduate students will be trained via the proposed research using world-class research infrastructure in a collaborative, international group environment, with opportunities to develop technical research skills, communication skills, along with leadership and teaching opportunities.