Coupled thermo-fluid-structural dynamics and stability of rotating pipes conveying fluid flow

In this work, we introduce a new thermo-fluid-structure interaction formulation for the first time to study in a systematic manner the influence of thermal stress, gyroscopic force, and fluid dynamics inside the structure on the stability of rotating pipes. The governing equations of motion are formulated based on thermoelasticity theory and the Hamilton principle that considers flow-structure interaction and thermal expansion effects. The characteristic frequency equations of the system are established through the discretization of the governing partial differential equations using the Galerkin procedure. Various parametric studies are conducted to examine the influences of spinning speed, internal flow velocity, temperature increase, and thermal parameter on the vibration behavior and stability criteria of the system. It is observed that temperature effects play an important role in the dynamic response and stability of the system. Furthermore, in the absence of external excitations, high thermal parameters prolong the vibration period. For verifying the results' accuracy and credibility, the numerical results are further verified through comparison with the predictions made by the deep neural network (DNN) algorithm. It is important to note that the use of the DNN algorithm trained using our extensive parametric dataset makes it possible to create an accurate surrogate model that allows simulation of the current complicated system with much lower computational expense. It is clear that such integration of machine learning techniques not only verifies the physical trend found but will also serve as an efficient and fast tool for future research into even more complicated situations.