Dynamic Stress-Strain Prediction of Vibrating Structures in Operation

该项目的研究目标是将新的动力实验测量和计算模型相结合，以预测总体空间响应，最重要的是，内部结构成员如何响应外部诱导的动力荷载。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），机械故障并不明显，通常发生在结构表面与内部肋或加强构件之间的界面上。不幸的是，由于时变的环境、空气动力和操作载荷，目前还不能从测量数据中预测内部动态响应。提出的研究将检查在旋转时使用大量测量分布点的解析形状展开函数来预测复杂节理界面的内部动态应力-应变信息，其中经常发生破坏。这种方法还将能够估计目前无法测量的外部施加的分布力。建模方法可以应用于几乎任何具有复杂关节界面的结构，通过使用减少的测量自由度来询问或监视结构。年代的完整性。提出的研究是一项新技术，将实现旋转结构在运行中的全场动态测量，从而提高对叶片在飞行中的结构响应的理解。参与的研究生和本科生都将了解当前对工业界和学术界重要的研究领域。分析工具可以用来创建视觉刺激的数据，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受众的兴趣进行定制，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强有力的推广工作，以激励妇女和K-12学生对科学和工程产生兴趣。

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.