In the dynamics of turbomachinery the mechanical damping of the blading has been in the focus of research for the last three decades to improve the dynamic performance in terms of high cycle fatigue issues. Actual designs with highly optimized geometry with respect to maximum efficiency and less contact interfaces (e.g. blisks) may need additional damping to avoid high vibration amplitudes at forced excitation near resonance. In the former and current research a strong emphasis is put on friction based damping strategies with good results but also minor disadvantages (e.g. strong nonlinearity, change of contact conditions caused by wear). Hence, also novel damping techniques are considered for the vibration amplitude reduction of turbine blading, for example piezoelectric shunt damping and blade coatings.
展开▼
