Fatigue Failure Analysis of Twisted Blade

• Madan Kumara M C

  English

  Author

• Nandish. R. V

  English

  Author

Usually turbine blades fail due to the various forces acting on the blade during operation in
which centrifugal forces is important. The effect of centrifugal forces on the turbine blade is very important in
the evaluation of life of the blade. In turbine blades due to the large centrifugal forces the blades susceptible to
high cycle fatigue frequently. Sometimes the failure of the turbine blade is eliminated by the design. This can be
achieved by twisting the turbine blades and the blade’s cross section varies throughout the length of the blade.
The root position of the blade is the region of interest because the stress concentration is high at the root of the
blade. Here the failure analysis is done by creating the notches on the leading edge of the blade. In this paper
the effect of the notches on the twisted blade is presented. Here the notches are created at the leading edge at
different distances from the root of the blade. At the same time the size of the notches are also varied. Fatigue
analysis is done for the notched twisted rotating blade, alternating stress, stress intensity, strain energy and life
of the blade is found.

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