Numerical Study of Fluid-Structure Interaction of the UHBR ECL5/CATANA Fan

With the increasing use of composite materials in fan blades, the analysis of fluid-structure interaction (FSI) phenomena has become essential to improve both knowledge of flow physics and the influence on performance and stability limits. Experimental test cases become a key element by offering reference data under realistic operating conditions in order to validate advanced CFD methods and fine-tune existing numerical models. As a result, the development of modern fan architecture requires dedicated experimental benchmarks to provide representative geometries. For this reason the ECL5/CATANA test case, reflecting upcoming Ultra High Bypass Ratio (UHBR) engine configuration, has been developed and studied through an experimental campaign at École Centrale de Lyon (ECL). An extensive experimental investigation has been conducted providing a comprehensive database of high-quality aerodynamic and aeromechanical measurements. This work presents a detailed numerical investigation of the fan stage aerodynamics. The study has been carried out using the CFD code TRAF, developed at the University of Florence. To have a deeper understanding of multi-physics coupling mechanisms, flutter simulations and unsteady runs near stall margin have been performed to characterize self-induced vibration and Non-synchronous vibration (NSV) respectively. This paper aims to evaluate and predict the onset of instabilities driven by fluid-structure interaction. The numerical results are analysed and compared with experimental data, demonstrating the accuracy of the proposed numerical model.