Development of a Vibration-based Acoustic Sound Power Measurement Method

多达4000万成年美国人因噪音过大而听力受损，3000万美国人每天都暴露在有害的噪音中。作为一个社会，我们越来越意识到我们周围过度的噪音，以及它造成的不适和健康问题。为了解决这个问题，工程师和设计师需要在产品设计过程中包括噪声测试数据的有效方法。目前测量声功率的标准和方法需要专门的声室，因此声功率测试通常既昂贵又耗时。声功率是用来量化产品产生的噪声的度量标准。因此，声功率测试甚至可能不会进行，这限制了设计师关注和减少产品噪音的能力。这项研究的重点是开发一种新的基于振动的声功率测量方法，使工程师能够有效地获取和使用噪声数据来改进他们的产品。新方法不受当前声功率测量标准的许多限制，可以用于真正的现场测量，为公司节省大量时间并提供改进的产品。有许多测量声功率的标准。然而，这些通常有限制，如需要特定的声场，反射表面，没有变化的背景噪声。一种新的基于振动的方法将被开发出来，旨在克服这些限制。这种新方法将结构视为一组小而独立的辐射体，并通过计算辐射体之间的自阻抗和互阻抗来估计声功率。对于简单的理想结构，已经给出了这些阻抗的表达式。本研究将利用这些表达式来验证从振动测量中获得声功率的方法。然后，它将专注于开发理论和计算工具，以解释任意形状的结构，耦合的建筑结构和建筑结构的组件。通过将扩展计算工具的结果与现有标准的结果进行比较，将对这些更复杂的结构进行新方法的实验验证。通过克服当前标准的一些限制，新方法也将用于真正的原位测试。新方法并不意味着取代所有其他方法，但它将提供一种实用的基于振动的替代方法。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

As many as 40 million adult Americans have hearing loss from loud noise and 30 million Americans are exposed to hazardous noise levels every day. As a society, we are becoming more aware of excessive noise around us, and the discomfort and health problems it creates. To address this problem, engineers and designers need efficient methods to include noise test data in the product design process. Current standards and methods for measuring sound power, which is the metric used to quantify noise produced by a product, require specialized acoustic chambers such that sound power testing is typically expensive and time consuming. As a result, sound power testing may not even be done, which limits the ability of designers to focus on and minimize noise in their products. This research will focus on developing a new vibration-based sound power measurement method that will allow engineers to efficiently acquire and use noise data to improve their products. The new method is not limited by many of the restrictions of current sound power measurement standards and can be used to make truly in situ measurements saving companies significant time and providing improved products.A number of standards exist for measuring sound power. However, these typically have restrictions such as requiring specific acoustic fields, reflective surfaces, and no varying background noise. A new vibration-based method will be developed that is designed to overcome a number of these restrictions. This new method treats the structure as an array of small, individual radiators, and estimates the sound power through the calculation of self- and mutual-impedances between the radiators. Expressions for these impedances have been developed for simple ideal structures. This research will utilize these expressions to validate the method of obtaining the sound power from vibration measurements. It will then focus on developing the theoretical and computational tools to account for arbitrarily shaped structures, coupled built-up structures, and components of built-up structures. Experimental verification of the new method will be carried out for these more complex structures by comparing results using the extended computational tools with results from existing standards. By overcoming some of the restrictions of current standards, the new method will also be used for truly in-situ testing. The new method is not meant to replace all other methods, but it will provide a practical vibration-based alternative.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.