Gas Turbine Handbook : Principles and Practices

56 Gas Turbine Handbook: Principles and Practices
Figure 4-5. Velocity components relative to airfoil.
Figure 4-6. Compressor system curve.
are limited in the centrifugal forces they can withstand. Blade vibration
is just as complex. There are three categories of blade vibration:
Resonance, Flutter, and Rotating Stall. They are explained here.
Resonance—As a cantilever beam, an airfoil has a natural frequency
of vibration. A fluctuation in loading on the airfoil at a frequency
that coincides with the natural frequency will result in fatigue
failure of the airfoil.