Dynamic Stress-Strain Prediction of Vibrating Structures in Operation

该项目的研究目标是将新的动态实验测量和计算模型相结合，以预测总的空间响应，最重要的是，内部结构构件对外部诱导的动力荷载的反应。对于许多复杂的复合材料结构(如风力涡轮机、直升机叶片和其他大型柔性结构)，机械失效在外部并不明显，通常发生在结构表面与内部肋骨或加强件之间的界面处。不幸的是，由于时变的环境、空气动力学和操作载荷造成的内部动态响应目前无法根据测量数据进行预测。这项拟议的研究将研究在旋转时对大量测量的分布点使用解析形状展开函数，以预测经常发生故障的复杂接头界面的内部动态应力-应变信息。这种方法还将能够估计目前无法测量的外部应用的分布力。这种建模方法几乎可以应用于任何具有复杂节点界面的结构，方法是使用较少的测量自由度来询问或监测结构--S完整性。这项拟议的研究是一项新技术，将能够对运行中的旋转结构进行全场动态测量，从而更好地了解叶片在飞行中的结构响应。参与的研究生和本科生都将获得对当前对工业和学术界重要的研究领域的欣赏。分析工具可以用来创建视觉刺激数据，将设计决策的效果与振动响应联系起来，音乐和体育的例子可以根据不同观众的兴趣量身定做，以展示科学研究如何为我们的日常生活做出贡献。在以往成功的基础上，将利用动画图像相关数据开展一项强有力的外联工作，以激励妇女和K-12年级的学生对科学和工程感兴趣。

The research objective of this project is to integrate novel dynamic experimental measurements and computational modeling to predict the total spatial response and most importantly, how internal structural members respond to externally induced dynamic loads. For many complex composite structures (e.g. wind turbine, helicopter blades and other large flexible structures), mechanical failure is not externally apparent and typically occurs at the interfaces between the structure's surface and the internal ribs or stiffening members. Unfortunately, the interior dynamic response due to time-varying environmental, aerodynamic, and operating loads is not currently predictable from measured data. The proposed research will examine the use of analytical shape expansion functions for a large number of measured distributed points while rotating to predict interior dynamic stress-strain information at intricate joint interfaces, where failure often occurs. Such an approach will also enable the estimation of the externally applied distributed forces that are currently not measurable. The modeling approach can be applied to virtually any structure that has intricate joint interfaces by using a reduced number of measured degrees of freedom to interrogate or monitor a structure?s integrity. The proposed research is a new technology that will enable full-field dynamic measurement of rotating structures in operation, resulting in an improved understanding of the structural response of blades in flight. Both graduate and undergraduate students involved will gain an appreciation for current research areas important to industry and academia. The analytical tools can be used to create visually stimulating data that connects the effect of design decisions to the vibration response, and examples from music and sports can be tailored to the interest of different audiences to show how scientific research can contribute to our everyday lives. A strong outreach effort, building on previous successes, will be implemented using the animated image correlation data to motivate women and K-12 students to become interested in science and engineering.