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Comparison of the aerodynamic damping ratio of turbine blades
| Object | Aerodynamic damping ratio ζa [-] | Source |
|---|---|---|
| SO-3 turbine blades (free-standing) | 0.14% (calculated) | Formulas (Eqs. 1 and 2) |
| High pressure turbine blades of Honeywell TFE 731-2 engine (free-standing) | 0.14%–0.26% (±0.11%) | Kielb & Abhari, 2001 |
| Steam turbine blades (free-standing) | 0.21%–0.40% | Brown, 1981 |
Comparison of the impact of friction dampers on blade vibrations_
| Object | Amplitude reduction (%) | Source |
|---|---|---|
| SO-3 turbine (free-standing blades, baseline under-platform dampers) | -62.0 | Klepacki, 1975 |
| SO-3 turbine (free-standing blades, optimized under-platform dampers) | -74.0 | Moneta, 2019 |
| Axial compressor (free-standing blades, roller under-platform dampers) | -80.0 | Hanson, 1956 |
| Volvo RM6/RM8 turbine (freestanding blades, under-platform dampers) | -80.0 | Csaba, 1997 |
| Steam turbine (last stage blades coupled by damping bolts) | -83.3 | Szwedowicz, 2008 |