Linear stability analysis in rotating frames and its application to fan blade transition prediction

Lucas Pascal (1) , Raphael Barrier (2) , Gilles Billonet (2) , Julien Marty (2)

1 DMPE, ONERA, Université de Toulouse [Toulouse]
2 DAAA, ONERA, Université Paris-Saclay (COmUE) [Châtillon]

The in-house linear stability solver of ONERA has been extended to rotating frames. The theoretical details of linear stability theory in rotating frames are given. Validation is performed by comparing against the well-known Ekman layer case. Moreover, two new compressible validation cases are proposed for which very good agreement is as well obtained. Linear stability analysis is then performed on a flow around a rotating fan blade, obtained by means of RANS computation. By neglecting or taking into account rotation in the linear stability equations, the effect of rotation on transition mechanisms is investigated. Moreover, N-factors are computed for transition prediction. The present results show that rotation hardly modifies the growth-rate of Tollmien-Schlichting instabilities. However, rotation destabilizes stationary cross-flow waves but not enough to trigger transition.

Mots clés: Transition; Fan blade; RANS

Domaines: Acoustique [physics.class-ph]

Lucas Pascal, Raphael Barrier, Gilles Billonet, Julien Marty. Linear stability analysis in rotating frames and its application to fan blade transition prediction. AIAA Aviation 2018, Jun 2018, Atlanta, United States. pp.1-11, ⟨10.2514/6.2018-4215⟩. ⟨hal-03163196⟩