Reducing Vibration and Wind Loads in Tall Buildings Using Fluidic-based Aerodynamic Modification (FAM)

使用基于流体的空气动力修改 (FAM) 减少高层建筑的振动和风荷载

• 批准号: 1200987
• 负责人: Chris Letchford
• 金额: $ 21.08万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1200987&HistoricalAwards=false
• 关键词: Reducing; Vibration; Wind; Loads; Tall

This research aims to develop a revolutionary approach to the shaping of tall buildings to reduce their wind loading. The concept is to use Fluidic-based Aerodynamic Modification (FAM), where wind flow is modified around the building by the injection of fluid flow in strategic locations, to improve the aerodynamic 'shape' of a structure. These fluid interventions will modify the local flow such that the building experiences reduced wind loads. Active Flow Control is now being widely used in the aeronautical world to improve flow characteristics over airfoils; its application to bluff bodies, such as buildings, to reduce response is novel. The objectives of the proposed research are to demonstrate the feasibility of the FAM approach in reducing response; to investigate the fundamentals of jet/flow and flow/structure interaction both through their impact on the loading on the building and on the flow patterns around it; and to assess the efficiency of steady and periodic forcing of the injected flow in terms of their response reduction and invested energy. The research will build on industry funded wind tunnel tests undertaken at the Center for Flow Physics and Control (CeFPaC) at Rensselaer for FAM on streamlined bodies such as airfoils on planes and wind turbines. This project will provide proof of concept of the approach and whether FAM has the potential to improve tall building design. By 2050 it is anticipated that the World's population will have increased by 50% to around 9 Billion and that the majority of that increase will occur in urban areas. The current pressure on urban land has led to tall buildings being the dominant building form in densely populated cities and has stimulated urban regeneration in the last two decades of the 20th Century. However, the majority of new urban developments, especially with respect to tall building typologies, have not followed principles of environmental and/or sustainable design. While the development and increased use of light-weight and high-strength materials in the construction of these buildings has provided them with reduced mass, it has increased their susceptibility to dynamic wind load effects. Thus the gains afforded by incorporating these new materials into tall buildings are countered by the need to focus much more attention on their habitability under strong wind conditions. For most tall, slender buildings the design is governed by both the strength and serviceability (human habitability). The significance of controlling the aerodynamic performance of a structure solely by the manipulation of the flow over its surface with fluidic intervention has huge potential impact on global energy and resource consumption. Extending the definition of a body beyond the solid edge boundary of geometry to include the fluid around it, will redefine other dynamic relationships between engineered structures and the flow they are immersed in, and impact heat and mass (humidity) transfer, potential energy harvesting, pollutant capture, noise reduction, indoor air management, etc. This will allow tall buildings to become adaptive to their external environment and provide a safer and a healthier indoor environment, while decreasing construction costs and energy expenditure. A team of four faculty members, two each from engineering and architecture will work together on this project. The educational plan proposes strengthening STEM for 6-8 graders through extending the focus on airflow to the urban scale by designing a city based on wind flow studies within the framework of the national Future Cities Competition.

这项研究旨在开发一种革命性的方法来塑造高层建筑，以减少风荷载。这个概念是使用基于流体的空气动力学改造（FAM），通过在战略位置注入流体来改变建筑周围的气流，以改善结构的空气动力学“形状”。这些流体干预将改变当地的流动，使建筑经历减少风荷载。主动流动控制在航空领域被广泛应用于改善翼型的流动特性。将其应用于建筑物等钝体以减少响应是新颖的。拟议研究的目标是证明FAM方法在减少反应方面的可行性；研究射流/流动和流动/结构相互作用的基本原理，通过它们对建筑物的载荷和周围流动模式的影响；并根据响应减小和投入能量来评估注入流的稳定和周期性强迫的效率。这项研究将建立在工业界资助的风洞试验的基础上，该试验由伦斯勒流动物理与控制中心（CeFPaC）在飞机和风力涡轮机的翼型等流线型体上进行。该项目将证明该方法的概念，以及FAM是否有潜力改善高层建筑设计。到2050年，预计世界人口将增加50%，达到90亿左右，其中大部分增长将发生在城市地区。当前对城市土地的压力导致高层建筑成为人口密集城市的主要建筑形式，并在20世纪的最后20年刺激了城市的更新。然而，大多数新的城市发展，特别是高层建筑类型，并没有遵循环境和/或可持续设计的原则。虽然在这些建筑的建设中，轻质和高强度材料的发展和使用增加了它们的质量，但它增加了它们对动态风荷载影响的敏感性。因此，将这些新材料结合到高层建筑中所带来的收益被需要更多地关注它们在强风条件下的可居住性所抵消。对于大多数高大、细长的建筑来说，设计是由强度和适用性（人类可居住性）共同决定的。仅通过流体干预操纵表面流动来控制结构的气动性能对全球能源和资源消耗具有巨大的潜在影响。将物体的定义扩展到几何体的固体边缘边界之外，包括其周围的流体，将重新定义工程结构与其所浸入的流动之间的其他动态关系，并影响热量和质量（湿度）传递，势能收集，污染物捕获，降噪，室内空气管理等。这将使高层建筑能够适应外部环境，提供更安全、更健康的室内环境，同时降低建筑成本和能源消耗。一个由四名教师组成的团队，分别来自工程和建筑专业，他们将共同完成这个项目。该教育计划提议，在全国未来城市竞赛的框架内，通过设计一个基于气流研究的城市，将对气流的关注扩展到城市规模，从而加强6-8年级学生的STEM。