Numerical Simulation and Experimental Verification on the Effects of Vibration Suppression of HPT Blades

This paper aims to investigate the effects of the prism-type under-platform damper (PTUPD) for the high pressure turbine (HPT) blade using theoretical analysis and experimental approaches. The investigated HPT blade has witnessed a rupture failure at the root during the engine test. A thorough failure analysis was performed to identify the failure mode. Furthermore, the crack propagation simulation was carried out to deeply understand the failure mechanism. High cycle failure (HCF) characteristics were observed and the crack initiation life accounted for more than 80% of the total propagation life. Afterwards, the response with the deliberated PTUPD structure was compared with the baseline in both simulation and test. Results show that the maximum response was about 0.45 mm using the PTUPD whereas the response for the baseline reached 0.72 mm. Meanwhile, the frequency has shifted from 3050 to 3150 Hz, moving away from the resonance region. Dynamic response was measured by performing the rotational excitation test and a 60% stress reduction was observed with the PTUPD mounted. Finally, the parametric analysis results reveal that the additional vibration suppression effects is negligible when the PTUPD mass exceeded 6 g.