Problematics of aerodynamic damping calculation from measured data of 5-blade cascade

0564701 - ÚT 2023 CZ eng C - Conference Paper (international conference)
Šnábl, Pavel - Pešek, Luděk - Prasad, Chandra Shekhar - Chindada, Sony
Problematics of aerodynamic damping calculation from measured data of 5-blade cascade.
Plzeň: Západočeská Univerzita, 2022. In: COMPUTATIONAL MECHANICS 2022. Plzeň: University of West Bohemia Plzeň, 2022 - (Adámek, V.; Jonášová, A.; Plánička, S.; Zajíček, M.), s. 145-146. ISBN 978-80-261-1116-0.
[Conference on COMPUTATIONAL MECHANICS 2022 (CM 2022) /37./. Srní (CZ), 07.11.2022-09.11.2022]
R&D Projects: GA ČR(CZ) GA20-26779S
Institutional support: RVO:61388998
Keywords : aerodynamic damping * S-curve * blade cascade
OECD category: Applied mechanics
https://www.kme.zcu.cz/compmech/download/proceedings/CM2022_Conference_Proceedings.pdf#section*.45

Aerodynamic damping as a function of inter-blade phase angle (IBPA), so called S-curve, is crucial for assessment of aeroelastic stability of blade cascades, e.g. turbines, compressors, etc.
For constructing the S-curve, the motion-induced controlled flutter is introduced to the bladesof the cascade. As decribed in [1], two testing methods exist: aerodynamic influence coefficient
(AIC) approach and travelling wave mode (TWM) approach. In TWM approach, all blades in a row oscillate with the same frequency and amplitude with various IBPAs. The response is
measured only on the reference blade. With this approach, several measurements with different IPBAs are needed to construct the S-curve. On the other hand, AIC uses single oscillating
blade and principle of linear superimposition of aerodynamic influence responses measured on all blades in a cascade. The result of one single measurement can be used for estimation of
aerodynamic damping for any IBPA. In the past year a new 5-blade cascade with rotating symmetrical NACA 0010 profiles was designed and built. The blades of the cascade were placed further apart and thus we are now able to reach stall flutter. Also, the suspension of the blades and sensors were significantly improved. Now, our goal is to evaluate S-curves using AIC approach for different flow conditions and oscillation frequencies.
Permanent Link: https://hdl.handle.net/11104/0340717