The One-shot Aeroelastic Method: a Highly Efficient Modeling Approach Based on the Harmonic Balance Technique
Date of Award
Doctor of Philosophy
Hans DeSmidt, Vasilios Alexiades, Jay Frankel
In this work, a highly efficient and robust partitioned aeroelastic approach, called the One-shot method, is developed for the solution of dynamic aeroelastic problems in a novel way. Based on the state-of-art harmonic balance solution technique, the One-shot method features multiple prominent advantages. First, this novel approach resolves both of the fluid and structure fields by integrating respective harmonic-balance forms of governing equations in pseudo-time, and variables of both fields are converged simultaneously in one run of the solver. This eliminates the need to sweep over aeroelastic parameters which is necessary in traditional frequency-domain methods, and significantly reduces the cost of aeroelastic analyses. Second, the computational cost becomes independent of the number of the structural modes retained in the analysis which offers substantial computational efficiency over traditional aeroelastic solution techniques. Third, the solution of two fields (fluid and structure) do not need to be time-synchronized unlike what is required in traditional time-accurate approaches. This allows each field to use respective optimal physical time steps (different number of harmonics), different (optimal) pseudo-time steps, as well as different integration techniques (explicit or implicit) to achieve the fastest convergence rates. Last but not least, the One-shot method is flexible in the sense that either the flow field variable (velocity) or the structural variable (amplitude of vibration) can be taken as the input, which enables the One-shot method to predict unstable limit-cycle-oscillations as well as flutter boundary. The One-shot method has been validated and verified on various two- and three-dimensional benchmark aeroelastic systems of different number of degrees-of-freedom in different flow regimes, offering a promising tool to the field of dynamic aeroelasticity.
Li, Hang, "The One-shot Aeroelastic Method: a Highly Efficient Modeling Approach Based on the Harmonic Balance Technique. " PhD diss., University of Tennessee, 2019.