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

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

1 DMPE, ONERA, Université de Toulouse [Toulouse]
2 DAAA, ONERA, Université Paris Saclay [Meudon]

A linear stability solver has been extended to rotating frames. The theoretical details of the 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 well obtained. Linear stability analysis is then performed on a rotating fan blade with incoming flow, which is obtained by means of a Reynolds-averaged Navier–Stokes 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 crossflow waves, but not enough to trigger transition.

Mots clés: Transition; Rotation; Fan; Linear stability; Clean Sky joint undertaking; European Union; H2020

Domaines: Sciences de l'ingénieur [physics]; Physique [physics]

Lucas Pascal, Raphaël Barrier, Gilles Billonet, Julien Marty. Linear stability analysis in rotating frames and its application to fan blade transition prediction. AIAA Journal, 2020, pp.1-8. ⟨10.2514/1.J059101⟩. ⟨hal-02860231⟩