Tuned Mass Dampers & Absorbers

The first step is to determine whether the undesired vibration should be attacked with a tuned vibration absorber (TVA) or a tuned mass damper (TMD). In general,

• If the vibration response is dominated by a single frequency that is the same frequency as a nearby motor, pump or other disturbance source, a TVA is probably appropriate. The idea is to make the structure more difficult to move at that frequency.
• If the vibration response is dominated by a single frequency, and that frequency corresponds to a resonance or structural mode, then a TMD is more appropriate. A properly designed and tuned TMD will add damping to the offending mode, reducing overall response.

The most important parameters for specifying either type of device are:

• Dominant frequency of the vibration
• Geometry and approximate mass of the vibrating structure
• Available volume and mass for the vibration suppression device (TMD or TVA)
• Environmental constraints such as the thermal environment
• Any additional dynamic or quasi-static loading on the structure, for example whether it is spinning
• Constraints on use of particular materials

With most or all of these parameters understood, it is usually possible for Moog CSA to determine the type and feasibility of tuned vibration devices for vibration suppression in the specific application.