Bluff-Body Flutter Derivatives via CFD

通过 CFD 计算 Bluff-Body Flutter 导数

• 批准号: 9123354
• 负责人: Robert Scanlan
• 金额: $ 11.01万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-02-15 至 1996-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9123354&HistoricalAwards=false
• 关键词: Bluff; Body; Flutter; Derivatives; via

The present project hinges around a central concept known as "flutter derivatives" which are quantities that need to be identified in certain aerodynamic contexts. Such derivatives arise, for example, in regard to a body placed in a cross-wind flow, where the dimensionless form of the aerodynamic lift, drag or moment is given by a coefficient C that changes according to the angle of inclination of the body. The flutter derivatives C' prove to be of key importance in the response of bluff structures- like long bridges- to wind, as their characteristics clearly define the possible proclivity of the bridge to become unstable in the wind. Focusing on the engineering design of bridges, knowledge of the coefficients C' for bridge deck forms has heretofore been acquired exclusively by means of wind tunney experiment. Now, however, with advances in computational fluid dynamics, the possibility arises of acquiring knowledge of C' via calculation alone. such studies lie in the realm of research and development, and a back-and-forth exchange between calculation and wind tunney experiment is needed.//

本项目围绕一个中心概念， “颤振导数”是需要 在特定的空气动力学环境中识别。 此类衍生物 例如，对于放置在侧风中的物体， 流动，其中无量纲形式的气动升力，阻力 或力矩由系数C给出，该系数C根据 身体的倾斜角度。 颤振导数C'证明是关键的重要性， 海崖结构（如长桥）对风的响应， 特征清楚地定义了可能的倾向 桥在风中变得不稳定。 专注于桥梁的工程设计， 迄今为止，已经获得了桥面板形式的系数C 完全通过风洞实验。 然而，随着 随着计算流体动力学的发展， 仅仅通过计算就能获得C'的知识。 这种研究属于研究和开发领域， 计算与风洞间的来回交换 实验是必要的。