Amplification of Excitation in Fatigue Analysis of Compressor Blades by Improving Fixture Design using Transmissibility Parameter

This paper presents the effects of dynamic properties of the fixture, especially transmissibility in experimental fatigue analysis. Endurance limit extraction of structures demands large stresses to be applied. Therefore, high power equipment would be needed for excitation. Improving fixture design considering dynamic properties can lead to the same stress levels by using lower power shakers. In this paper transmissibility feature of the designed fixture is enhanced, so that the generated motion by shaker is amplified and transferred to the structure being tested, which is a compressor blade. The procedure involves fixture modeling and implementation of numerical simulation for natural frequency determination. Knowing the first natural frequency of the blade, transmissibility value is extracted using theoretical equations. After achieving the desired magnification, the fixture is fabricated and experimental tests are performed.