An Innovative Design Concept for Noise and Vibration Control

在许多应用中，需要材料和结构阻尼，其中抑制不需要的动态位移可能是至关重要的。虽然主动控制可以提供这种抑制，但与主动系统相关的复杂性和成本惩罚降低了它们的吸引力。被动材料和结构阻尼可以提供显著的好处。该研究旨在确定一种诱导被动阻尼的创新机制的潜力。在结构单元中诱导阻尼的经典方法是使用约束粘弹性材料（VEM）块。VEM在受到动态应力时耗散能量。在传统的方法中，VEM和在其中添加的结构都是寄生的附加物。其创新之处在于在约束VEM内诱导应力的方法，同时保持较高的结构效率。通过调整复合结构材料的弹性特性，可以在VEM内部产生应力，以增强系统阻尼，同时保持所需的刚度特性。该创新技术还允许在一个结构元件中使用多个VEM层，从而在更宽的频率和温度范围内进行阻尼。研究的初始阶段将解决用于桁架型结构的材料，但创新可以应用于一系列结构元件，为噪声和振动控制方面的竞争进步创造机会；例如，用于机械、运输车辆、土木结构等。

Material and structural damping is required in many applications wherein suppression of unwanted dynamic displacements can be critical. While active control can provide such suppression, the complexity and cost penalties associated with active systems reduce their attractiveness. Passive material and structural damping can provide significant benefits. The research is aimed at identifying the potentials of an innovative mechanism for inducing passive damping. A classical method for inducing damping in a structural element is the use of patches of constrained visco-elastic material (VEM). The VEM dissipates energy as it is dynamically stressed. In the conventional approach, both the VEM and the structure added to induce stresses therein are parasitic additions. The innovation addressed is in the method for inducing stress within the constrained VEM while retaining high structural efficiency. By tailoring the elastic properties of composite structural materials, stress can be induced within the VEM to enhance system damping while maintaining required stiffness properties. The innovation also allows for multiple VEM layers within a structural element allowing for damping over extended frequency and temperature ranges. The initial phase of the research will address materials for use in truss type structures, but the innovation can be applied to a range of structural elements creating opportunities for competitive advances in noise and vibration control; e.g., for machinery, transportation vehicles, civil structures, etc.