Validation of a Modal Work Approach for Forced Response Analysis of Bladed Disks

TitleValidation of a Modal Work Approach for Forced Response Analysis of Bladed Disks
Publication TypeJournal Article
Year of Publication2021
AuthorsPinelli L, Lori F, Marconcini M, Pacciani R, Arnone A
JournalApplied Sciences
Date Published06/2021
ISSN Number2076-3417
Accession NumberWOS:000666063400001
Other NumbersScopus 2-s2.0-85108362118
Keywordsblade vibration, cyclic symmetry, forced response, forcing decomposition, modal work
The paper describes a numerical method based on modal work approach to evaluate the forced response of bladed disks and its validation against numerical results obtained by a commercial FEM code. Forcing function caused by rotor/stator interactions are extracted from CFD unsteady solution properly decomposed in time and space to separate the spinning perturbation acting on the bladed disk in a cyclic environment. The method was firstly applied on a dummy test case with cyclic symmetry where the forcing function distributions were arbitrarily selected: comparisons for resonance and out of resonance conditions revealed an excellent agreement between the two numerical methods. Finally, the validation was extended to a more realistic test case representative of a low pressure turbine bladed rotor subjected to the wakes of two upstream rows: an IGV with low blade count and a stator row. The results show again a good agreement and suggest to compute the forced response problem on the finer CFD blade surface grid to achieve a better accuracy. The successful validation of the method, closely linked to CFD  environment, opens the opportunity to include the tool on an integrated multi-objective procedure able to account for aeromechanical aspects.
Refereed DesignationRefereed