Prediction and Control of Interface Damping in Built-up Structures

建筑结构界面阻尼的预测和控制

• 批准号: 1462870
• 负责人: Melih Eriten
• 金额: $ 25.16万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1462870&HistoricalAwards=false
• 关键词: Prediction; Control; Interface; Damping; Built

Interface damping is a primary source of energy losses in built-up structures such as weapon systems, space vehicles, aircrafts, ships, automobiles, buildings, bridges, and turbine engines. Accurate prediction and control of interface damping is critical for safety, reliability and energy efficiency of built-up structures operating in dynamic conditions. Interface damping results mainly from frictional energy losses over contacting surfaces. Variability, nonlinearity and uncertainty in contact interactions limit the ability to accurately predict and model interface damping. This research project aims at identifying the main mechanisms that govern interface damping, its magnitude and its nonlinear characteristics. The project will investigate and outline effective methods to adjust such characteristics to desired values. Results from this award will enable designs of structural interfaces with desired interface damping. The expected outcome is the improvement of safety, reliability and energy efficiency of built-up structures. The results from the research will be shared with the community and K 12, undergraduate and graduate students through design projects involving vibrations and acoustics of simple built-up structures.Time and load dependent stochastic interfacial events introduce nonlinearity to interface damping, and deter predictability of dynamical response. The current state-of-the-art in estimating interface damping is through phenomenological models, which cannot ensure predictive results for untested conditions. Physics-based models cannot account for all possible events and changes occurring at the interfaces. This research offers an effective alternative to complicated modeling whereby the mismatch of elastic properties across interfaces are adjusted, and loading conditions are identified to reduce and if possible eliminate nonlinearities and variability in interface damping. Additional benefit of this alternative approach is the ability to tune interface damping over several orders of magnitude based on operational needs. The research approach is a concerted effort in modeling and experimentation that bridges two distinct disciplines such as tribology and structural dynamics. The PI will systematically study interfacial mechanics, geometry, friction, material properties and loading conditions to identify the major contributors to interfacial energy dissipation. Built-up structures containing interfaces with controlled material properties, preloads and geometries will be designed and constructed. Finally, forced and free vibrations tests will be performed on the built-up structures to explore tunable interface damping in dynamic response. An education and outreach program will also be conducted to disseminate the research results to a broader audience, and introduce important concepts of damping and friction to the students at various stages of their education process.

界面阻尼是武器系统、航天器、飞机、船舶、汽车、建筑物、桥梁和涡轮发动机等组合结构中能量损失的主要来源。界面阻尼的准确预测和控制对于动态条件下运行的建筑结构的安全性、可靠性和能源效率至关重要。界面阻尼主要由接触表面的摩擦能量损失引起。接触相互作用的可变性、非线性和不确定性限制了准确预测和建模界面阻尼的能力。该研究项目旨在确定控制界面阻尼、其大小及其非线性特性的主要机制。该项目将研究并概述将这些特性调整到所需值的有效方法。该奖项的结果将使能够设计具有所需界面阻尼的结构界面。预期成果是提高建筑结构的安全性、可靠性和能源效率。研究结果将通过涉及简单建筑结构的振动和声学的设计项目与社区和 K 12、本科生和研究生分享。依赖于时间和载荷的随机界面事件引入了界面阻尼的非线性，并阻碍了界面阻尼的可预测性。动态响应。目前估算界面阻尼的最先进方法是通过唯象模型，这不能确保未经测试的条件下的预测结果。基于物理的模型无法解释界面上发生的所有可能的事件和变化。这项研究为复杂建模提供了一种有效的替代方案，通过调整界面弹性特性的不匹配，并确定加载条件，以减少甚至消除界面阻尼的非线性和可变性（如果可能的话）。这种替代方法的另一个好处是能够根据操作需求将界面阻尼调整几个数量级。该研究方法是建模和实验的共同努力，将摩擦学和结构动力学等两个不同的学科联系起来。 PI 将系统地研究界面力学、几何形状、摩擦、材料特性和负载条件，以确定界面能量耗散的主要因素。将设计和建造包含具有受控材料特性、预载和几何形状的界面的组合结构。最后，将对组合结构进行受迫振动和自由振动测试，以探索动态响应中的可调界面阻尼。还将开展教育和推广计划，向更广泛的受众传播研究成果，并向处于教育过程各个阶段的学生介绍阻尼和摩擦的重要概念。