Fatigue life estimation of tuned vibration absorbers with response estimation method

Yılmaz, Yunus
Tuned Vibration Absorbers are designed and used in applications where any unwanted vibration is needed to be elimination from a vibrating system. In order to accomplish that goal TVAs are needed to be designed to absorb vibrational energy on its own at a specified frequency. Since the energy is absorbed from main system to the TVA, this energy will cause high vibration levels on the TVA. Due to the excessive vibration that occurs on the TVA, vibrational fatigue life is a concern for TVA design. Vibrational fatigue life tests or analyses can be carried out during design phase of the TVA. However, for the systems that are not easy to test or analyze because of its size or complexity, response estimation methods are required to ease calculation or testing of fatigue life of the TVA during design phase of it. Those response estimation methods are used to calculate response of the TVA as if it has attached to the main structure. Since the response of the TVA could be acquired from the estimation, fatigue life analysis or tests can be carried with the response that is estimated. Computational or testing time is saved with response estimation method. A previously developed response estimation method is evaluated and verified for fatigue life analysis and tests in this thesis. Two types of TVA have been designed for a basic structure as the first part of the thesis study. Those two types are cantilever beam type TVA and helical spring and mass type TVA. In order to design the TVAs modal analyses have been carried out for both main structure and TVAs. When design of the TVAs is finished, next step of the thesis study is to conduct fatigue life estimation analyses of whole structure that is main structure with TVA and only TVA with utilizing response estimation method. Effectiveness of response estimation method for estimating fatigue life of the TVA is compared by using analysis results. Furthermore, fatigue life experiments have been carried out for the beam type TVA design. Evaluation of the results that are acquired from analysis with utilization of response estimation method and whole structure are compared with the test results to compare analysis results with real life test. Hence, effectiveness of the response estimation method to estimate fatigue life of the TVAs is evaluated with analyses and tests.


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Citation Formats
Y. Yılmaz, “Fatigue life estimation of tuned vibration absorbers with response estimation method,” M.S. - Master of Science, Middle East Technical University, 2022.