TITLE:
Aeroelastic Analysis of a Transonic Fan Blade with Low Hub-to-Tip Ratio including Mistuning Effects
AUTHORS:
Zhizhong Fu, Yanrong Wang
KEYWORDS:
Aeroelastic Stability, Flutter, Turbomachinery, Mistuning
JOURNAL NAME:
Journal of Power and Energy Engineering,
Vol.3 No.4,
April
15,
2015
ABSTRACT:
This paper presents a comprehensive
investigation of aeroelastic stability for a high aft-swept transonic fan blade
with low hub-to-tip ratio. The evolution of the blade’s aeroelastic stability
in the first bending modes is studied. A 3D flutter computation representing
today’s industry standard is performed. Steady state flow field and
motion-induced unsteady pressures acting on the blade have been determined by a
3D Reynolds-Averaged Navier-Stokes (RANS) equations with a standard k-ε
turbulence model. A weakly coupled (one-way) method has been employed to describe
the interaction between fluid and structure. The results of aerodynamic damping
indicate a significant shock-driven risk. To increase the flutter margin by a
viable method, a statistical mistuned aeroelastic stability investigation has
been performed. It has been found that alternately intentional mistuning with a
small blade frequency offset stabilizes the system effectively. However, as the
standard deviation of random mistuning reaches some critical values, the
introduction of alternately intentional mistuning does not provide any additional
stabilizing effects.