Free Vibration and Elements of Shaft Dynamics

Industry relevance

The vibration margin is a fundamental design margin. The flexural and torsional vibration analysis is fundamental be it a shaft , a gear train or a seal. The design of bearing support structure is critical not only just for critical speed and as a source of damping but also critical but also for weight and space constraint (it may come in the gas path). The understanding of exciting agencies is critical to understand dynamic loading (HCF loading). Designing damping is critical to the life of several parts subject to vibration (designing the friction damping).

Example : Joint analysis for various material combinations.

Learning outcomes

Treated with matrices calculus and trigonometry

• Appreciation for all real time factors that influence the natural frequency of vibrations. (including stress stiffening, softening, gyrsostiffening temperature etc).
• Appreciation for critical speed of shafts and influence of bearing support structure
• Appreciation for critical speed of shafts and influence of bearing support structure
• Appreciation for designing physical damping, computing dynamic amplification factor hence dynamic stress.