T-tail transonic flutter wind tunnel test. Part 2: Numerical restitution

ifasd2024 Tracking Number 155

The paper presents the main results of the numerical restitution of the test campaign realized on a T-tail flutter model in subsonic and up to high transonic domains. The Wind Tunnel Tests were carried out in ONERA S2MA pressurized wind tunnel at the end of 2022 in the framework of the Clean Sky 2's Airframe ITD program and will be presented in a companion paper [1]. Numerical results obtained with high-fidelity fluid-structure coupling simulations performed using the elsA CFD solver (ONERA-Safran property) [2] are compared to wind-tunnel test data and to low-fidelity numerical results. Four configurations of T-tail were measured during the test campaign, in order to investigate the effect of yaw angle and dihedral on the flutter phenomenon. These different geometries enable also to assess the ability of our numerical tools to predict corner flow aerodynamic phenomena arising in the area of the T-tail surface intersections. A good correlation is obtained between numerical and experimental steady pressure coefficients, even at higher Mach numbers. For the unsteady pressure coefficients, the aerodynamic responses are computed for a forced motion applied to the T-tail model and the effects of different excitation parameters are assessed. Aeroelastic stability of a T-tail configuration is also investigated and coupled high-fidelity simulations are capable to predict the good evolution of the critical pressure with Mach number. Further work is still in progress and numerical and experimental results will be compared for the other T-tail flutter models. ACKNOWLEDGEMENTS This work has been funded within the frame of the Joint Technology Initiative JTI Clean Sky 2, AIRFRAME Integrated Technology Demonstrator platform "AIRFRAME ITD" (contract N. CS2-GAM-AIR-2020-945521) being part of the Horizon 2020 research and Innovation framework program of the European Commission. REFERENCES [1] Lanari V., Lepage A., Breus E., “T-tail transsonic flutter wind tunnel test – Part 1: Seal-ing system design and model testing”, IFASD 2024, Den Haag. [2] Cambier, L., Heib, S., Plot, S., “The ONERA elsA CFD software : input from research and feedback from industry”, Mechanics & Industry, 14(3): 159-174, 2013.