mass damper - vibration absorber
DESCRIPTION
A mass damper is a vibration absorber able to attenuate the vibrations of a structure or a machinery. By a mass damper it's possible to increase the global damping of the system without the necessity to modify the mechanical structure.TRANSCRIPT
Mass damper – vibration absorber
Eidos Engineering SRL
Mass damper development
A mass damper is a vibration absorber able to attenuate significantly the vibrations of a structure or a machine.
In the graph we report the frequency response of a machine with and without mass damper. The application of a mass damper gives an important increment of the global damping.
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0.9Mass damper action
Rotor speed [rpm]
Dis
plac
emen
t [m
m]
without mass damperwith mass damper
Frequency response measured on a vibrating machine
Fields of application
• Tool machines • Machine frames and chassis • Gears and transmissions • Stacks • Bridges and footbridges • Constructions • Energy generation plants • Wind turbines
Mass damper examples
Eidos Engineering develops and
supply new generation vibration
absorbers, designed according
to customer’s specifications.
Mass damper for a tool machine
Mass damper for a wind turbine Mass damper for a stack
A wide range of sizes is possible, starting
from few grams for electronic devices, up to
some tons, for structures such as bridges or
buildings.
Mass damper design Mass damper for a wind turbine
Natural frequency of turbine at 0.47Hz
Natural frequency of stack at 2.8Hz
Mass damper for a stack
Without mass damper
With mass damper
Without mass damper
With mass damper
Assembling and testing
Wire rope spring assembly
Mass damper during testing on bench test
Mass damper for structures
Dynamic analysis of a three stories structure. The graphs show the displacements of the structure under the 1976 Friuli earthquake without the application of a mass damper and with a mass damper placed at top. Friuli 1976 – Buja seismic station
Displacement of the structure at top
without tuned mass damper
Time [s]
Dis
plac
emen
t [m
]
with tuned mass damper
Time [s]
Dis
plac
emen
t [m
]
Advantages
• Up to 70% vibration reduction
• Up to 70% stress reduction
• Noise attenuation
• Increased security
• Opportunity to reduce weight and dimensions of mechanical structures
• Simplicity and reliability
Eng. Stefano Galassi, Ph.D. e-mail: [email protected]
mobile: +39 333 6907275
tel.: +39 0434 507547
fax: +39 0434 507546
web: www.eidosengineering.com
headquarters: via Roveredo 20/b 33170 Pordenone, Italy
Main contact